I get these are conjugate acid-base pairs. But is the end result of glycolysis pyruvic acid that then loses a hydrogen ion to make pyruvate? Or does glycolysis just go straight to pyruvate? Or does it depend? Same with lactic acid and lactate during lactic acid fermentation, and acetic acid and acetate during ethanol metabolism, etc.

Ok, so the question gives the molecule OH- and asks for the conjugate acid-base pair,
to which I said, alright, since OH- is clearly the base in the pair, we just need the acid, so we add an H which gets us H20.
The only thing that I'm stuck on is that the question then asks which is more likely to form in water.
My only guess is that we would look at the Ka and Kb values to see how each conjugate reacts with water, and see which is stronger to guess which conjugate would be more valuable in water.
When I googled the values of the Ka of water, I got 1*10^-14, and then I calculated the Kb of OH from the Ka value to give a value of 1, thus I think that H20 would be more likely to form in water as a conjugate since the high Kb value of OH- means it REALLY wants that proton, so it will just really want to turn into H20.
Is this correct thinking? Thank you so much in advance, I'm just really trying to understand this concept!!

Hello! I have my chemistry finals in a few days and I wanted to ask for help on what to study from the following topics. I’ve memorized all necessary formulas but I need to keep a refresher in case I missed anything. All help is appreciated, thank you very much!
P.S. I’m not sure if this belongs here but if it doesn’t, please feel free to delete!
Gases: - Convert between atm and mm Hg - STP conditions? - Molar volume? When is molar volume the same for any gas? - Dalton’s Law - Avogadro’s Law of Constant Volumes calculations - Graham’s Law calculations
Solutions/Solubility: - Calculate molarity given mass and molar mass. - Calculate mass or volume of a compound given molarity and volume or moles. - Calculate the ion concentrations in solution (Ex. What is the concentration of Li in a 0.200 molar solution of Li3PO4?) - Strong acid (monoprotic) with Strong Base titration calculation .
Oxidation / Reduction: - Identify the oxidized and reduced species in a redox reaction. - Identify the oxidizing agent and reducing agent. - Balance a redox reaction in an acidic or basic solution.
Acid / Base Theory: - Define Bronsted, Lewis, and Arrhenius acids and base concepts. - Identify Bronsted conjugate acid base pairs. - Calculate pH, pOH, [OH-], or [H3O+], using Kw or pKw (14), given the concentration of a strong acid or base. - Calculate either pH, [H3O+], pOH, or [OH-] in a weak acid or weak base equilibrium. - Know when it is appropriate to use quadratic equation. - Calculate Ka or Kb given pH or pOH. - Predict the products of acid-base reactions.
Thermochemistry: - Define endothermic and exothermic in the context of heat energy and enthalpy values (+ or - ). - Use Hess’s law to solve for overall enthalpy.
Chemical Equilibrium: - Identify what conditions define chemical equilibrium, as well as what conditions do NOT define chemical equilibrium. - Write the equilibrium expression given an equilibrium reaction. - Calculate Keq given all equilibrium concentrations (no ICE table needed). - Calculate an equilibrium concentration given all other equilibrium concentrations AND Keq. - Calculations using ICE tables. - Identify concentration increases or decreases, as well as reaction shifts, when an equilibrium reaction is disturbed (Le Chatelier’s Principle).
Electrochemistry: - Electrolysis - Electroplating - Galvanic cells / Voltaic Cells

Can someone pleaseeee explain the relationship between conjugate acid-base pairs when using strong/weak acid and strong/weak bases and provide examples? I can't seem to wrap my head around it!!

Are my thoughts correct? acetate ion is a weak base when it reacts with water. But, it only can be a strong conjugate base when it is in the conjugate acid-base pairing for the reaction CH3COOH +H20 < CH3COO- +H3O+? For the Na+ ion in its conjugate acid-base pairing, NaOH +H20 OH- + Na+ ,it is considered a weak conjugate acid. But, when Na+ ion reacts with water, it does not react because Na+ is a spectator ion? and it is neutral? In summary, the conjugates of something does not determine the strength of an acidic ion or basic ion when it reacts with water?

In a video I was watching there was a problem that states that the Ka of water is 10^-14.
I thought that the kw of water is 10^-14 and therefore the Ka would have to be 10^-7 since Ka * Kb = kw.
Also confused why the Ka * kb of conjugate acids and bases = kw. Is this true for all conjugate acid/base pairs?
Any insight on these topics would help ty.

Disclaimer

I am not a doctor! Please don’t sue me, I’m already poor!
 

Lesson 1.4: Acids and Bases

 
Hey, everyone! We just spent seven lessons learning about biology, so I thought you guys deserved a break...
 
...WITH CHEMISTRY!!!
^{she says as groans echo throughout the classroom.}
 
But seriously.
You know I like to be unnecessarily thorough in explaining things to you guys. So before we begin talking about the acid mantle, pH, and all that crap, I think it would be helpful to start with a full understanding of what an acid (and its counterpart, a base) actually is. Besides, learning the science behind these words might help your brain get a better grip on all the posts out there about pH testing your products.
 
^{And here you all were thinking today’s lesson would be about the acid mantle since you took the time to look at the syllabus. Ha! Joke’s on you!}
 

Slappin’ the Base...s and Acids

 
You’re probably already familiar with acids and bases, thanks to school and some general life experience. You might even be able to guess which category a substance would fall into.
 

Acid	Base
Tastes sour	Tastes bitter
Feels like stinging or burning	Feels slippery
Has a pH below 7	Has a pH above 7
Examples: Lemons, vinegar, and sometimes pee	Examples: soap, toothpaste, Tums, bleach, ammonia

Fun Fact: The word “acid” comes from the Latin word acere, which means “sour”!
 
But, of course, it’s not that simple! There’s got to be more to defining an acid or base than just tasting and touching one. After all, if there wasn’t, we’d have a lot of dead chemists trying to figure out just how basic that bleach might be.
Luckily for us (and our chemists), there are currently three accepted theories out there that are used to define acids and bases, none of which involve licking things.
 
The Arrhenius Theory, proposed by the Swedish chemist Svante Arrhenius in 1884:

• Acids are substances that produce hydrogen ions (H⁺) in solution.
• Bases are substances that produce hydroxide ions (OH^-) in solution.

The Brønsted-Lowry Theory, proposed by Danish chemist Johannes Nicolaus Brønsted and English chemist Thomas Martin Lowry in 1923:

• An acid is a proton (H⁺) donor.
• A base is a proton (H⁺) acceptor.

The Lewis Theory, proposed by American chemist Gilbert N. Lewis in the same year as the Brønsted-Lowry theory, 1923:

• An acid is an electron pair acceptor.
• A base is an electron pair donor.

 
See? Acids and bases are sooo simple. I mean, just explained them in only 6 bullet points! It all makes sense now, so I can move onto a section about your skin, right?
Wait, what? No?!
Well...crap...I wasn’t really prepared for this…ummm... :(
 
Just kidding!
^{But honestly, how many of you were hoping I’d actually move on? Slackers!}
 

Atoms and Elements

 
If your first question upon reading those six bullet points was, “Arrhenius, wtf is a hydrogen ion?” then I’m gonna have to assume that you need a little refresher course on atoms and elements.
You probably recognize hydrogen from your foggy memories of being forced to study the periodic table during science class. It’s the first element on the periodic table, represented by an H, and has one proton.
 
Fig. 1, Hydrogen
 
For those of you with really foggy school memories, or you younger readers who haven’t taken chemistry yet, an element is a name given to the simplest form of a substance (as in, you can’t break it down any further into simpler substances) made of one type of atom.
And an atom is the absolute smallest possible piece of an element, retaining all of the properties of that element. Atoms are composed of these three subatomic particles:

• Protons are particles that carry a positive electrical charge.
• Electrons carry a negative electrical charge.
• Neutrons don’t carry a charge at all. They’re neutral.

The protons and neutrons of an atom can be found clustered together at its center, forming its nucleus, while the electrons orbit around the nucleus.
 
Fig. 2, An Atom
 
The number of protons in an atom is what defines which element it belongs to.
For example, let's say you're holding a brick of gold. Every single atom in that gold brick will have 79 protons. If each atom only has 78 protons, then lucky you, because you’re actually holding a brick of platinum.
This is why the number of protons found in the atom of an element is listed so prominently on the periodic table. (Hint: it’s called an atomic number.)
So really, you could just refer to “hydrogen” as “all atoms with 1 proton in them,” and the “Periodic Table of Elements” could just be called the “Periodic Table of the Types of Atoms.”
 
Additionally, there will be the exact same number of electrons as there are protons in any normal atom.
So in your bar of gold, each atom has 79 protons and 79 electrons. You know a hydrogen atom has 1 proton, so you can correctly guess that there’s 1 electron as well.
 
But Arrhenius didn’t say that acids produce hydrogen. He said they produce hydrogen ions, and I still haven’t explained what those are.
Remember how I said that a normal atom has an equal number of protons and electrons? Well, an ion occurs when an atom gains or loses an electron, off-setting that tidy 1:1 ratio.
A positive ion is when an atom loses an electron, and is represented by a ⁺.
A negative ion, also called an anion, is when an atom gains an electron, represented by a ^-.
 

The Arrhenius Theory

• Acids are substances that produce hydrogen ions (H⁺) in solution.
• Bases are substances that produce hydroxide ions (OH^-) in solution.

 
Now, a hydrogen atom only has one proton, one electron, and no neutrons. So when we take away its electron, giving us H⁺, that means we are left with one lonely proton. (This is why the symbol for a proton is also H⁺.)
So when Arrhenius says that an acidic substance will produce hydrogen ions in solution, this means that an acid, when added to water (the solvent in our solution), will increase the amount of lonely protons present.
 
For an example, let’s see how hydrogen chloride (HCl) would work within the Arrhenius theory:
 
Fig. 3, HCl as an Arrhenius Acid
 
When put in water, the hydrogen chloride dissociates (meaning, it "splits up") into a hydrogen ion and a chlorine ion, because the chlorine (Cl) took an electron from the hydrogen.
 

• State Symbols
  You may have noticed (g) and (aq) sitting beside our HCl in Figure 3. Those little parentheticals are known as state symbols or phase symbols -- symbols that tell you the state (or phase) of matter of the chemicals involved in a reaction. There are four state symbols you’ll come across when studying chemistry; one for each of state of matter, and one for chemicals mixed in water:
  
  • (g) for gas
  • (s) for solid
  • (l) for liquid
  • (aq) for aqueous solution (meaning the chemical is dissolved in water)
  • And while plasma is definitely a state of matter, it is exceptionally rare to find an equation that uses chemicals in a plasma state, so it doesn’t really have or need a state symbol.
  Hydrogen chloride is a gas, so our chemical equation in Figure 3 began with HCl(g). But since our equation involved dissolving the gas in water, it becomes an aqueous solution and receives an (aq).
  And by the way, once hydrogen chloride is in an aqueous solution, it will start being referred to as hydrochloric acid.
  Hydrochloric acid will continue to use the nickname of HCl, since it is still the same chemical it was before it met up with some water, after all. However, this means that when you spot HCl in an equation, the only way you’ll know which version is being referred to is if the chemist who wrote the equation was kind enough to include a state symbol.
  

 
An Arrhenius base, when added to water, will increase the amount of hydroxide ions (OH^-) present. The OH means that there is an oxygen (O) atom bound to a hydrogen atom.
For an example, we’ll use sodium hydroxide (NaOH):
 
Fig. 4, NaOH as an Arrhenius Base
 
Here, the sodium (Na) dissociates from the hydroxide, leaving us with a sodium ion and a hydroxide ion.
 
According to the Arrhenius theory, neutralization (the acid and base cancel each other out when combined) happens because hydrogen ions and hydroxide ions react to produce water:
 
Fig. 5, Arrhenius Neutralization
 

The Brønsted-Lowry Theory

• An acid is a proton (H⁺) donor.
• A base is a proton (H⁺) acceptor.

 
While Arrhenius’ theory was doing fine for nearly 40 years, some chemists noticed there were a few problems with it. Amongst a variety of other issues, a major one was that his theory could only be applied to substances that dissolved in water, specifically. Another major problem was ammonia.
Ammonia (NH₃) is a base that many of you are familiar with. It can neutralize hydrochloric acid. But did you notice that NH₃ is missing an O? According to Arrhenius, a base needs to release OH^- when mixed with water, but ammonia doesn’t have any OH to give!
 
The Brønsted-Lowry theory doesn’t cancel out the Arrhenius theory; it simply broadens the definition of acids and bases to give them some more wiggle room.
Hydroxide ions are still bases because they’ll steal hydrogen ions from acids to form water. It’s just that, now, a base doesn’t need to have OH, it just needs the ability accept protons.
And the definition of an acid didn’t change much at all -- an acid just needs to continue being capable of giving hydrogen ions away.
 
The Brønsted-Lowry theory also points out a rather important detail that Arrhenius missed: there's no such thing as a lonely proton.
When hydrogen chloride is dissolved in water to make hydrochloric acid, the dissociated H⁺ isn’t just floating around. The HCl donates its proton to a water molecule, making water a base here. This produces hydronium ions (H₃O⁺).
 
Fig. 6, HCl as a Brønsted-Lowry Acid
Fig. 7, Depiction of HCl as a Brønsted-Lowry Acid
 
So, in reality, acids don’t actually increase the amount of H⁺ in an aqueous solution, because H⁺ doesn’t enjoy the singles life. What's really happening is that acids are increasing the amount of H₃O⁺.
 
According to the Brønsted-Lowry theory, neutralization simply happens when an acid donates a proton to a base, and the end result doesn’t necessarily have to be water.
This solves the Arrhenius theory’s “only in water” problem. As an example, when hydrogen chloride gas is neutralized with ammonia gas, it doesn’t make water. It creates ammonium chloride, a salt.
 
Fig. 8, Neutralization Resulting in a Salt
 
To neutralize our HCl example from Figure 6, we could add a hydroxide ion base. The HCl already donated its proton to water and made a hydronium ion. When we add our hydroxide ion base, the hydronium ion will donate its newly stolen proton to the hydroxide ion, which will end up making water.
 
Fig. 9, Brønsted-Lowry Neutralization
Fig. 10, Depiction of Brønsted-Lowry Neutralization
 
When the HCl previously gave its H⁺ to a water molecule and produced a hydronium ion, the water was behaving as a base. Here, the hydronium ion handed that newly acquired proton over to OH^-, so the water in this instance is acting as an acid.
That’s right; water is an acid and a base. This means that water is amphoteric; it's a substance that can behave either way.
 
With the Brønsted-Lowry theory, our ammonia problem is...no longer a problem. Ammonia can now officially call itself a base because it accepts protons.
If our acid is in a solution, ammonia will accept the proton from a hydronium ion just like a hydroxide ion would.
 
Fig. 11, Ammonia as a Brønsted-Lowry Base
 
Another helpful addition that Brønsted and Lowry gave to the understanding of acids and bases was that we can now measure their strength with greater accuracy.
With their theory comes the concept of conjugate acid-base pairs. This concept stems from the idea that the reactions of acids or bases are reversible.
To show you what I’m talking about, let’s use an acid called HA. The H is hydrogen, and the A is just a filler (sort of like x or n in algebra). We’re gonna put HA in water:
 
Fig. 12, HA Reaction in Water
 
From left to right:

• HA is an acid. It’s donating a proton to water and becomes an A ion.
• Water is a base. It’s accepting a proton from HA and becomes a hydronium ion.

But when you read it from right to left:

• The hydronium ion is an acid. It’s donating its proton back to the A ion.
• The A ion is a base. It’s accepting its old proton from the hydronium ion.

 
This reversible reaction means we actually have two acids and two bases within one reaction, and that is the basis of a conjugate pair:
 
Fig. 13, Conjugate Pairs
 
Here, we have H₂O as a base and H₃O as its conjugate acid. And we have HA as our acid and A^- as its conjugate base.
 
How does this tell us about the strength of an acid or base?
If our imaginary acid, HA, is a strong acid, then its reaction in water is gonna go from left to right, and it is unlikely that this reaction will spend any time going from right to left. If HA is a strong acid, its molecules will be almost completely ionized when it is in a solution.
A strong acid will give almost 100% of its hydrogen atoms to water molecules and won’t take any of them back, whereas a weak acid is only willing to part with some of its hydrogen atoms. Likewise, a strong base will accept almost 100% of the hydrogen atoms available, while a weak base will be less accommodating.
Vinegar (CH₃CO₂H) is considered a weak acid because, when mixed with water, less than 0.4% of its molecules will dissociate into H₃O⁺ and CH₃CO₂^- ions. Hydrochloric acid, on the other hand, is considered a strong acid because it almost completely dissociates.
Fun Fact: You probably have some nice, strong HCl hiding under your bathroom sink! It’s an ingredient often included in toilet bowl cleaners, like this one.
 

The Lewis Theory

• An acid is an electron pair acceptor.
• A base is an electron pair donor.

 
The Lewis theory, yet again, does not cancel out either of the previous two theories. It was meant to be a theory that would also broaden Arrhenius’ definition of acids and bases.
Rather than thinking of a base as something that accepts a proton, Lewis looked at it from a different angle. A Lewis base is donating a pair of its electrons to that lone proton.
Likewise, a Lewis acid is accepting that electron pair, so of course our hydrogen ions are still acids.
 
Let’s consider how our favorite bases function within this theory; hydroxide ions, ammonia, and water:
 
Fig. 14, Lewis Bases
 
See? Sure, they all accepted a proton. But from another angle, they each donated a pair of their electrons for the proton to attach to. It's easy to see how the Lewis theory is completely fine co-existing with the other two theories.
 
So it co-exists just fine, but is it really any different from Brønsted and Lowry’s theory?
It does sort of seem like Lewis came up with a theory just like theirs, but with some rewording. However, the Lewis theory actually managed to broaden the acid-base definition even further.
According to the Lewis theory, any time that an empty electron pair binds to another molecule, the electron donor is a base, and the acceptor is an acid. A lonely proton isn’t necessary to the Lewis theory.
For an example of how this changes things, let’s look at ammonia reacting with boron trifluoride (BF₃):
 
Fig. 15, BF₃ as a Lewis Acid
 
The ammonia is still acting like a base here. But instead of accepting a hydrogen ion (there aren’t any!), it’s donating an electron pair to the boron.
Within the Lewis theory, the boron trifluoride can be considered an acid, whereas there was nothing acidic about it, as far as Arrhenius, Brønsted, and Lowry were concerned.
 

A Final Note: What is a Scientific Theory?

 
When we use the term theory in regards to science, it doesn’t hold the same meaning as it would in day to day conversation. The term hypothesis would be much closer in meaning to the colloquial use of “theory”, but they still aren’t quite the same thing.
 
To quote CBLF from an ELI5 thread on the subject:

A scientific theory is a substantiated and testable explanation for a variety of observations and facts; it also makes predictions about the future. It is often modified to reconcile new facts, but it can also become obsolete when a new scientific theory is proposed that can explain more observations and facts than the previous one.
A hypothesis is a testable, reproducible and falsifiable statement that has to be refuted by experiments and/or observations. In other words, one must be able to test it multiple times and see if it is false. If it turns out that the hypothesis is true (e.g. "phenomenon X is correlated with phenomenon Y"), then it can be extended (e.g. "Is phenomenon X correlated with phenomenon Z?") and/or inserted into the relevant scientific theory.
A theory in everyday use is a guess, conjecture.

 
So, unlike a colloquial theory, a scientific theory is not simply a “guess”. A hypothesis is a guess, but it is a guess that can be tested.
 
Now maybe you’re wondering, if a scientific theory isn’t a guess, then why aren’t they called facts or laws?
A fact is a true observation (e.g. When I kick this ball, it moves). A scientific law is a short description of an observation, often using math (e.g. Newton’s Third Law of Motion: “to every action there is an equal and opposite reaction” or Fab = -Fba).
Scientific theories aren’t laws and they cannot become laws because they are entirely different things. Laws simply describe what’s happening in an observation, they don’t explain it. Theories are there to answer the hows and the whys of a law or a fact.
 
ѧѦ ѧ ︵͡︵ ̢ ̱ ̧̱ι̵̱̊ι̶̨̱ ̶̱ ︵ Ѧѧ ︵͡ ︵ ѧ Ѧ ̵̗̊o̵̖ ︵ ѦѦ ѧ ︵͡︵ ̢ ̱ ̧̱ι̵̱̊ι̶̨̱ ̶̱ ︵ Ѧѧ ︵͡ ︵ ѧ Ѧ ̵̗̊o̵̖ ︵ ѧѦ ѧ
 
Hello, readers!
It's been a while since my last lesson. You can thank the holidays for that!
You might also be able to thank the fact that I seriously hate having to study chemistry so I've been procrastinating pretty badly on this lesson...but that's beside the point!
 
I have BIG NEWS, though!
You can now sign up to receive an email every time I post a new lesson. Yippee! You can find the sign up form here, and I will be adding this link to the syllabus as well. Yayyy!
 
Next Up: Lesson 1.5 - The pH Scale
 
Sources:
http://www.chemtutor.com/acid.htm http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch11/conjugat.php http://chemwiki.ucdavis.edu/Physical_Chemistry/Acids_and_Bases http://www.chemheritage.org/discoveonline-resources/chemistry-in-history/themes/electrochemistry/sorensen.aspx

Going over the study guide, with a question that asks me to find the conjugate acid/base pairs of a given reactant. Now, I know how to find these, but am curious at the equations given by my teacher.
For some with an acidic reactant, she'll include H2O as a reactant as well, resulting in the formation of H3O+, and for some, she won't, producing H+. Should H2O be included in the reactants? Is there a rule I should follow? Or does it not matter?
Edit: here are two contrasting examples:

1. HC2H3O2 H+ + C2H3O2-
2. HI + H2O H3O+ + I-

• Labs
• Strong acids (HCl, HBr, HNO3, H2SO4, HI, HClO4) and strong bases (NaOH, KOH, group 2 cations + OH-)
• Solubility rules
• Nernst equation: E = E° - (0.0592/n)logQ
• Gibb's free energy: ΔG = ΔG° + RTlnQ
• Negative ΔG = favorable, positive ΔG = not favorable
• Rate law graphs to be linear (0 order: rate vs [A], 1st order: rate vs ln[A], 2nd order: rate vs 1/[A])
• Conjugate acid-base pairs (HA + H2O -> H3O+ + A-)
• Kp = Kc(RT)^Δn

I can't think of any more lol. You guys add some.

Hi, I cannot seem to find anywhere a straightforward answer to how to figure out at what pH a particular buffer solution will buffer. I am given a buffer system of equal concentrations NH3 and NH4+. I've used the Henderson-Hasselbach eq to calculate the pH of the sol'n to be 9.3. However, my notes from class suggest that the same exact equation in the same exact form:

pH = pKa + log ([A-]/[HA])

gives the pH at which the solution buffers. So is it true that the pH of a buffer solution, by itself, is the pH at which is buffers? I don't believe this to be the case because a conjugate acid/base pair should have a buffering affect at a certain range of pH, both above and below the pH of the buffer itself.
EDIT: I merely need to find if the system buffers in the acidic,basic or neutral range. So I don't need an exact pH. I'm assuming it's buffering in the basic range because the buffer's pH is basic? Or would it be the opposite?

A

Adnate - Where the gills or tubes under the cap of a fungus are perpendicular to the stipe or stem at the point of attachment
Adnexed - Where the gills or tubes under the cap of a fungus sweep upwards before being attached to the stem
Aerial mycelium - Hyphal elements growing above the agar surface.
Agar - An extract from a seaweed used to solidify media. The agar used in mushrooms cultivation is usually available in powder form
Agaric - A term describing mushrooms and toadstools having gills beneath a cap that is connected to a stipe or stem
Alkaline - Having a pH greater than 7.
Annulus - A ring of tissue left attached to the stem of a mushroom or toadstool when the veil connecting the cap and stem ruptures as the young fruitbody develops.
Antibiotic - A class of natural and synthetic compounds that inhibit the growth of or kill other microorganisms.
Ascomycetes - A group of fungi that have in common that they produce their sexual spores inside specialized cells (asci), which usually contain eight spores.
Aseptic - Sterile condition: no unwanted organisms present
Aseptic technique - Also sterile technique. Manipulating sterile instruments or culture media in such a way as to maintain sterility.
Autoclave - Basically a big pressure cooker, sometimes operating at higher pressure than 15 PSI, thus achieving sterilization temperatures above 250?F.
Axenic - Not contaminated; gnotobiotic: Said esp. of a medium devoid of all living organisms except those of a single Species

B

Bacteria - Unicellular microorganisms that may cause contamination in culture work. Grain spawn is very easily contaminated with bacteria. On the other hand there are some bacteria that are needed for the fruiting of agaricus. These are present in the casing soil.
Basidiomycetes - A group of fungi which produce their spores externally on so called basidia. Often four spores are produced per basidium. Many basidiomycetes show clamp connections on their hyphae, ascomycetes never do. Most mushrooms are classified as basidiomycetes, whereas most molds are ascymycetic.
Basidium (pl. basidia) - A cell that gives rise to a basidiospore. Basidia are characteristic of the basidiomycetes.
Biological efficiency - The definition of biological efficiency (BE) in mushroom cultivation is: 1 pound fresh mushrooms from 1 pound dry Substrate indicates 100 % biological efficiency. This definition was first used by the agaricus industry to be able to compare different grow setups and Substrate compositions. Note that this is not the same as true thermodynamic efficiency. The BE of Psilocybe cubensis is easily somewhere in the range of 200%uFFFDbr>
Birthing - Removing the fully colonized growth medium (like a cake from its jar) from whatever container it was kept in for colonization purposes and placing in an environment conducive to fruiting.
Bolete - A group of fungi having tubes rather than gills beneath the cap
Brown Rice Flour (BRF)- Ground brown rice. Many cultivators grind their own brown rice in a coffee grinder.
Buffer - A system capable of resisting changes in pH even when acid or base is added, consisting of a conjugate acid-base pair in which the ratio of proton acceptor to proton donor is near unity. An example is gypsum, which is an additive that increases a material's pH while helping to buffer it, or keep it within a desriable (and higher) pH range.

C

CaCl2 - Calcium chloride (Brand names: Damp-Rid, Damp-Gone, Damp B Gone, Damp Away). See desiccant.
CaCO3 - See calcium carbonate.
Calcium sulfate - CaSO4. See gypsum.
Carbon dioxide - CO2. A colorless, odorless, incombustible gas. Formed during respiration, combustion, and organic decomposition.
Carpophore(s) - Commonly known as "mushrooms", the reproductive organs of the true body of the fungus, formed by the web of mycelium that colonize a substrate.
Casing - Some mushrooms need a covering layer of soil with a specific microflora for Fruiting. Casing materials include peat and vermiculite; additives include calcium carbonate, calcium hydroxide (hydrated lime) and crushed oystershells.
CaSO4 - Calcium sulfate. See gypsum.
Cellulose - Glucose polysaccharide that is the main component of plant cell walls. Most abundant polysaccharide on earth, and common source of nourishment for cultivated fungi.
Clone - A population of individuals all derived asexually from the same single parent. In mushroom cultivation placing a piece of mushroom tissue on agar medium in order to obtain growing mycelium is called cloning. This is not strictly related to the colloquial notion of cloning, and is simply a manipulation of the natural asexual reproduction system of fungi.
CO2 - See carbon dioxide
Cobweb mold - Common name for Dactylium, a mold that is commonly seen on the casing soil or parisitizing the mushroom. It is cobweb-like in appearance and first shows up in small scattered patches and then quickly runs over the entire surface of the its substrate.
Coir - Coco coir. A short coarse fiber from the outer husk of a coconut. Used as a casing ingredient. Brand names include Bed-A-Beast .
CVG aka Coir Verm Gypsum- This commonly used acronym is one of the most commonly used substrates for growing Psilocybe Cubensis. CVG can be sterilized or pasteurized unlike other substrates that would otherwise require pasteurization and can't be sterilized with the intention of spawning to bulk in open air. Coir, Coir Verm, Coir Gypsum, and Coir verm gypsum are all usable combinations.
Colonization - The period of the mushroom cultivation starting at Inoculation during which the mycelium grows through the Substrate until it is totally permeated and overgrown.
Compost - Selectively-fermented organic material. Compost is one desirable substrate for mushrooms, but may vary in its components.
Coniferous - Pertaining to conifers, which bear woody cones containing naked seeds. Relevant in mushroom hunting.
Contamination - Undesired foreign material (contaminants), frequently organisms, in a growing medium. Often the result of insufficient sterilisation or improper sterile technique.
Cottony - Having a loose and coarse texture. Referred to a growth pattern of some fungi species or strains.
Culture - A sample of a given (generally desired) organism. In mycology, mushroom mycelium growing on a culture medium.
Culture medium - The material upon which a culture is developed. Micro-organisms differ in their nutritional needs, and so large number of different growth media have been developed, PD(Y)A (potato dextrose(yeast extract) agar) and MEA (malt extract agar) can be used for most cultivated mushrooms.

D

Deciduous - Trees and plants that shed their leaves at the end of the growing season. Relevant in mushroom hunting.
Desiccant - An anhydrous (moistureless) substance, usually a powder or gel, used to absorb water from other substances. Two commonly used dessicants are calcium hydroxide and silica gel. Dessication permits mushrooms to be preserved for extended periods.
Dextrose - A simple sugar used in agar formulations. Synonymous with glucose.
Dikaryotic mycelium - Contains two nuclei and can therefore produce fruiting bodies.
Diffusion - The movement of suspended or dissolved particles from a more concentrated region to a less concentrated region as a result of random movement on the microscopic scale. Diffusion tends to distribute particles uniformly throughout the available volume, given enough time, and occurs more rapidly at higher temperatures.
Disinfection - To cleanse so as to destroy or prevent the growth of microorganisms, usually referring to rubbing or spraying the surfaces one wants to disinfect with lysol, diluted bleach solutions or alcohol.

E

Endospore - A metabolically dormant state by which some bacteria become more resistant to heat, chemicals, and other adverse conditions. Given the proper conditions, they will reactivate (germinate) and begin to multiply. Many bacterial endospores cannot be destroyed at boiling temperatures. This is important to mycologists because grains contain a high number of dormant endospores, though rice often contains few to none; thus, many grains must be pressure cooked to achieve sterilization, whereas brown rice flour may simply be boiled.
Enzyme - A protein, synthesized by a cell, that acts as a catalyst for a specific chemical reaction.

F

Fermentation - Anaerobic (oxygen-less) decomposition. In mushroom cultivation, this often relates to composting. Easily-accessible nutrients may be degraded by micro-organism, making a substrate more selectively beneficial to the desired fungus. Unwanted fermentation may occur if the composted substrate is still very 'active' after inoculation or if thick layers or large bags are used. The latter may lead to low-oxygen conditions in parts of the substrate. Mushrooms are aerobic, meaning they need oxygen, while some undesirable bacteria thrive in anaerobic conditions.
Field capacity - Content of water, on a mass or volume basis, remaining in a soil after being saturated with water and after free drainage is negligible. Described as the state achieved when one can squeeze a handful of substrate or casing material hard, only to have one or two drops emerge.
Flow hood - A fan-powered and HEPA-filtered device that produces a laminar flow of contam free air. The air moves across the workspace allowing for open sterile work without the hassle and inconvience of a glove box.
Flush - The sudden development of many fruiting bodies at the same time. Usually there is a resting period between flushes.
Fractional sterilization - A sterilization method used to destroy bacteria and spores in preparation of grain spawn (rye, wheat, birdseed) requiring no pressure cooker. In this case, the jars fitted with a filter are boiled or steamed at 212?F (100?C) for 30 min in a covered pot, three days in a row. Between the boiling steps the jars are best kept warm, around 30?C, to allow the remaining endospores to germinate. The basic principle behind this method is that any resistant bacterial spores should germinate after the first heating and therefore be susceptible to killing during the subsequent boilings.
Fruiting - The process by which the mycelium produces fruiting bodies, or mushrooms, for the purpose of spore propagation (sexual reproduction).
Fruiting body - A mushroom. The part of the mushroom that grows above ground.
Fruiting chamber (FC) - A enclosed space with high humidity and fresh air exchange where mushrooms may fruit under proper conditions.
Fungicide - A class of pesticides used to kill fungi.
Fungus - A group of organisms that includes mushrooms and molds. These organisms decompose organic material, returning nutrients to the soil.

G

G2G - See grain-to-grain transfer. Inoculation of grain by already colonized grain.
Genotype - The set of genes possessed by an individual organism.
Geolite - One of several brand names/varieties of clay aggregate medium (also known as LECA for light expanded clay aggregate). It is a lightweight, porous substrate with excellent aeration.
Germination - The spreading of hyphae from a spore
Gills - The tiny segments on the underside of the cap. This is where the spores come from.
Glovebox - A glovebox is a device used to Isolate an area for work with potentially hazardous substances or materials which need to be free from direct contact with the outside environment for any reason. Most gloveboxes are small, tightly enclosed boxes having a glass panel for viewing inside and special airtight gloves which a person on the outside can use to manipulate objects inside.
Glucose - See dextrose.
Grain-to-grain transfer - The inoculation of grain with already-colonized grain. This procedure involves exposing uncolonized, sterilized grain, and so is prone to contamination. As such it should only be performed with a glove box, laminar flow hood, or similar device.
Gypsum - Calcium sulfate, CaSO4. A greyish powder often used in spawn preparation. It prevents the clumping of the grain kernels and acts as a basic pH buffer.

H

H2O2 - See hydrogen peroxide.
Hay - Grass that has been cut, left to dry in the field and then baled. It is fed to livestock through the winter when fresh grass is not available. The color of hay is greenish-grey. Not synonymous with straw.
HEPA - High Efficiency Particulate Air filter. A high-efficiency filter used in flow hoods.
Hydrogen peroxide - A clear aqueous solution usualy available in concentrations from 3%uFFFDo 30%uFFFDEasily decomposed into water and oxygen by enzymes like catalase, which is found in desirable mushrooms but not in many bacteria. This makes it capable of selectively destroying some competitors, and a tool sometimes used in cultivation. The mycological use of peroxide was the focus of a popular cultivation guide by Rush Wayne.
Hypha(e) - Filamentous structure which exhibits apical growth and which is the developmental unit of a Mycelium.

I

In vitro - From the Latin, in glass, isolated from the living organism and artificially maintained, as in a petri dish or a jar.
Incubation - The period after inoculation (preferably at a temperature optimal for mycelial growth) during which the Mycelium grows vegetatively
Inoculation - Introduction of spores or spawn into substrate
Isolate - A strain of a fungus brought into pure culture (i.e. isolated) from a specific environment

J

K

L

Lamellae - The gills of a mushroom
LC - See liquid culture
Lignin - A complex polymer that occurs in woody material of higher plants. It is highly resistant to chemical and enzymatic degradation. The white rot fungi are known for their lignin degrading capability.
Limestone - See calcium carbonate.
Liquid culture - A culture of mycelium suspended in a nutritious liquid, for use as an inoculant.

M

Magic mushroom - Any of a number of species of fungi containing the alkaloids psilocybin and/or psilocin. Common species are the 'liberty cap' (Psilocybe semilanceata) and Psilocybe cubensis, though there are dozens of others.
Maltose - Malt sugar, used in agar formulations.
Martha - Refers to a fruiting chamber based on a Martha Stewart-brand translucent vinyl closet.
MEA - Malt extract agar.
Metabolism - The biochemical processes that sustain a living cell or organism.
Multispore - Refers to an inoculation where multiple germinations and matings occur due to the use of various spores, as in a spore solution (e.g. spore syringe) and as opposed to an isolate. Liquid cultures may sometimes be called multispore (though they contain no spores) if they were produced from a spore solution, rather than an isolate.
Mycelium - The portion of the mushroom that grows underground. Plants have roots; mushrooms have mycelium. Mycelium networks can be huge. The largest living thing in the world is a single underground mycelium complex.
*Mycorrhiza# - A symbiotic association between a plant root and fungal hyphae.

N

O

Overlay - A dense mycelial growth that covers the casing surface and shows little or no inclination to form pinheads. Overlay directly results from a dry casing, high levels of carbon Dioxide and/or low humidity.
Oyster shells - See calcium sulfate.

P

Parasitic - Fungi that grow by taking nourishment from other living organisms.
Pasteurization - Heat treatment applied to a Substrate to destroy unwanted organisms but keeping a reduced concentration of favorable ones alive. The temperature range is 60?C to 80?C(140?F-175?F). The treatment is very different from sterilization, which aims at destroying all organisms in the substrate .
PDA - Potato dextrose agar.
PDYA - Potato dextrose yeast agar.
Peat - Unconsolidated soil material consisting largely of undecomposed, or only slightly decomposed, organic matter accumulated under conditions of excessive moisture. Used as casing ingredient in mushroom culture.
Perlite - Perlite is a very light mineral, often found next to the vermiculite in gardening stores. It has millions of microscopic pores, which when it gets damp, allow it to 'breathe' lots of water into the air, aiding in humidification, which is beneficial to fruiting. Peroxidated agar - Agar made with H2O2 for the purpose of retarding contamination by bacteria and new mold spores. Not suitable for use with ungerminated mushroom spores, only live mycelium. See also: hydrogen peroxide.
Petri dish - A round glass or plastic dish with a cover to observe the growth of microscopic organisms. The dishes are partly filled with sterile growth medium such as agar (or sterilized after they have been filled). Petri dishes are used to produce isolates.
PF - Psylocybe Fanaticus. The original spore provider and originator of the PF-Tek, one of the original home growing techniques on which many others are based.
pH - A measure to describe the acidity of a medium. pH 7 is neutral; higher means Alkaline, lower Acidic
Pileus - The cap of a mushroom.
Pinhead - A term to describe a very young mushroom, so-named for the pin-sized developing cap.
Polyfill - A polyester fiber that resembles synthetic cotton. Found at fabric stores, Wal-Mart, arts & craft stores. Also used as a filter medium for aquariums (filter floss). Used as a jar lid filter in preparation of grain spawn and for other filtration purposes.
Pressure cooker - A pot with a tight lid in which things can be cooked quickly with steam under higher pressure. The reason for it is that at 15 PSI (pound per square inch) pressure the water boils at a higher temperature (250?F, 121?C) than at ambient pressure.(212?F, 100?C). In mushroom cultivation used to thoroughly sterilize substrates and agar media.
Primordium - The initial fruiting body, the stage before pinhead
Psilocybin, Psilocin - Hallucinogenic organic compounds found in some mushrooms.
Pure culture - An isolated culture of a micro-organism, uncontaminated with others. Pure cultures are essential to the production of spawn because it is sensitive to contamination.

R

Rhizomorph - "Root-like". An adjective used to describe the appearance of the mycelium of some mushroom strains. Rhizomorphic mycelium is taken as a sign of fast colonization and qualities desirable for fruiting.
Rice cake - Many of the growing methods involve making a 'cake' of brown rice flour( BRF ), vermiculite and water, and injecting it with mushroom spores. Not a rice cake like you'd buy in a supermarket!
Rye - A hardy annual cereal grass related to wheat. Lat.:Secale cereale. In mushroom cultivation rye grain is used as spawn medium.
Ryegrass - A perennial grass widely cultivated for pasture and hay and as a lawn grass. Lat.:Lolium perenne. Seeds used as Substrate for P. mexicana and P. tampanensis.

S

Saprophyte - A fungus that grows by taking nourishment from dead organisms
Sclerotium - A hard surfaced resting body of fungal cells resistant to unfavorable conditions,which may remain dormant for long periods of time and resume growth on the return of favorable conditions.
Secondary metabolite - Product of intermediary metabolism released from a cell, such as an antibiotic.
Selective medium - Medium that allows the growth of certain types of microorganisms in preference to others. For example, an antibiotic-containing medium allows the growth of only those microorganisms resistant to the antibiotic.
Simmer - To cook just below or at the boiling point.
Slant - A test tube with growth medium, which has been sterilized and slanted to increase the surface area
Spawn - Culture of mycelium on grain, sawdust, etc., used to inoculate the final substrate, or bulk.
Spawn run - The vegetative growth period of the mycelium after spawning the substrate to bulk.
Species - Fundamental unit of biological taxonomy. Generally spoken, two individuals belong to the same species if they can produce fertile offspring
Spore print - A collection of spores taken from a mushroom cap, often collected on sterile card stock, aluminum foil, or some other flat surface.
Spore syringe - A solution of spores collected in a syringe, usually scraped from a spore print under sterile conditions. Several companies will sell you ready-to-use spore syringes for a few pounds/dollars. This site has links to, or address for, many of the most reputable of these companies.
Spores - Means of sexual reproduction for mushrooms and many other fungi. Comparable to a plant seed, save that spores combined sexually with one another after germination; there are no "male" and "female" spores as with seeds and pollen or sperm and eggs, but compatability is complicated. Spores are microscopic, and any visible clump of spores is in fact a collection of many thousands or millions of spores.
Stamets, Paul - The owner of Fungi Perfecti and mushroom guru. The co-author of The Mushroom Cultivator and many other helpful books.
Stem - The stipe or stalk of a growing mushroom.
Sterilization - Completely destroying all micro organisms present, by heat (autoclave, pressure cooker) or chemicals. Spawn substrate always has to be sterilized prior to inoculation.
Stipe - The stem of a mushroom at the top of which the cap or Pileus is attached
Strain - A genetic line considered to have common traits, usually identified for artificial selection by humans. Many strains have geographical names (e.g. Ecuador, Texan, Aussie), but point of natural origin is not necessarily the source of the name. Remember that strains are a human notion; vendors often differentiate between stocks that are not visibly different to everyone, but which have been perceived to have different characteristics, whether visual (e.g. the Penis Envy strain), chemical (as in strains perceived to have high potency), or behavioral (relating to the mushroom's response to environment, colonization speed, et cetera).
Straw - The dried remains of fine-stemmed cereals (wheat, Rye, barley...) from which the seed has been removed in threshing. Straw has a golden color.
Stroma - Dense mycelial growth without fruiting. Stroma occurs if spawn is mishandled or exposed to harmful petroleum-based fumes or chemicals. It also occurs in dry environments.
Substrate - Whatever you're using to grow the mushrooms on. Different varieties of mushroom like to eat different things (rice, rye grain, straw, compost, woodchips, birdseed). Different techniques involve infecting substrates with anything from spores, to chopped-up Mycelium, to blended mushroom.

T

Tek - Short for technique. Often prefaced with something to tell you what type of tek; e.g. PF-Tek, for Psylocybe Fanaticus Technique, one of the original home growing techniques on which many others are based.
Terrarium - A small enclosure or closed container in which selected living plants, fungi and sometimes small land animals, such as turtles and lizards, are kept and observed.
Tissue culture - Tissue cultures are the simplest way to obtain a mycelial culture. A tissue culture is essentially a clone of a mushroom, defined as a genetic duplicate of an organism. The basic procedure is to sterilely remove a piece of the mushroom cap or stem, and place it on an agar plate. After a week to ten days, Mycelium grows from the tissue and colonizes the agar. Great care should be taken to select a fruiting body of the highest quality, size, color, shape or any highly desired characteristic.
TiT - "Tub in Tub", refers to an incubator consisting of 2 plastic tubs and an aquarium heater.
Trichoderma - A common green mold.
Trip - What happens when you eat the finished product, if you are cultivating hallucinogenic varieties. With psilocybes, a trip tends to last from three to six hours. May range from mild visual effects and lightly enhanced perceptions, to a totally altered state of consciousness. Generally, this can be controlled to some degree by mindset, setting and dosage. Read some of the trip reports to get an idea of what other people have experienced before experiencing hallucinogens. Please always remember, although many of the effects seem to be experienced by many different people, you're going to have your trip, not someone else's.
Tyndallization - See fractional sterilization

U

Umbonate - Used to describe a cap with a raised central area above the point where the stipe meets the pileus

V

Veil - When a mushroom is growing, the edges of the cap are joined to the stem. As the mushroom grows larger, the cap spreads and the edges tear away, often leaving a very thin veil of material hanging from the stem.
Vermiculite - A highly absorbent material made from puffed mica. Used in rice cakes to hold water, and to stop the cake being too sticky. The mycelium likes room to breathe and grow.

W

WBS - Wild bird seed. Millet-based birdseed; used as spawn and Substrate in mushroom cultivation.

Z

Zonate - Marked with concentric bands of colour. Refers to the appearance of mycelium of some mushroom species on agar, for instance P. mexicana.

Hi all, I was helping my buddy do an orgo review session for his students, and there were some disagreements about H- or NH2- being a stronger base until we pulled up a pKa chart. I was curious if anyone could explain why. My buddy was thinking along the lines of conjugate acid base pairs, and how H2 wasn't hybridized because of the 1S orbital (or maybe it is, idk), whereas ammonia is SP3. I thought the hydride was more basic, he thought the NH2- was, and going by pKa values, they are close (H- pKa is ~35, NH2- pKa is ~36).
Any input would be appreciated.

I really don't understand acid base rxns very well, and am having trouble with this problem:
A solution is being made by dissolving sodium bicarbonate and sodium bisulfite in water.
a) Which of the two anions (HCO3- and HSO3-) is the stronger acid? Give your reasoning.
b) Predict the products of the reaction and write the equation
c) Identify the conjugate acid-base pairs in the rxn.
d) On which side will the equilibrium lie? Explain.
What I know is that Sodium Bicarbonate = NaHCO3 and Sodium Bisulfite = NaHSO3 How do I determine what is the stronger acid?

The following includes the examcraft mock paper for higher level chemistry. If you wish to go into the exam blind then obviously don't read this. This is an exhaustive list of main question topics and details of whats asked in each (as much as i remember and what i answered). If you wish to get an accurate representation of your subject knowledge for this mock i suggest that you stop reading now.
Section A
Question 1 Question 2 Question 3
Section B
Question 4 Question 5 Question 6 Question 7 Question 8 Question 9 Question 10 Question 11

If anyone can take just a few moments to explain some calculations for me, that would be awesome. Here's the problem:
Write the equation for the reaction that occurs when acetic acid is combined with sodium hydroxide. For a 1 M solution of acetic acid, calculate the pH of the resulting solution when 0.25, 0.5 and 0.75 molar equivalents of NaOH are added.
Can this be considered a buffer system even though it's not a conjugate acid/base pair and use the H-H equation?? Any Help is appreciated!!

Taken from my homework:
You have to prepare a pH 3.50 buffer, and you have the following 0.10 M solutions available: HCOOH, CH3COOH, ClCH2COOH, NaHCOO, NaCH3COO, and NaClCH2COO. Which solutions would you use? For the best system, calculate the ratio of the concentrations of the buffer components required to prepare the buffer.
(From Answer Key):
You need to recognize that there are three conjugate acid-base pairs present.

1. HCOOH/NaHCOO (pKa for HCOOH = 3.74)
2. CH3COOH/NaCH3COO (pKa for CH3COOH = 4.74)
3. ClCH2COOH/NaClCH2COO (pKa for ClCH2COOH = 2.85)

How exactly was the pKa calculated? Thanks.

I posted this question yesterday, and solved part of it with some help from people on here, but I just wanted to repost b/c the other thread was getting a little messy.
A solution is being made by dissolving sodium bicarbonate and sodium bisulfite in water.
a) SOLVED
b) Predict the products of the reaction and write the equation
c) Identify the conjugate acid-base pairs in the rxn.
d) On which side will the equilibrium lie? Explain.

Hi all, thank you for the help in advance!
I have to calculate the pH of a buffer without using the Hendersen-Hasselbach equation made from the pair 2.33M NH3 and 1.00M NH4Cl, with the assumption that the concentrations given are those in the final mixture. I get that buffers are made from conjugate acid/base pairs but I am not sure if I should try to make a balanced equation with water as a reactant and do an ICE table or try to calculate from K values or what. I am confused because it seems to me if the two concentrations are final, the problem implies that they are the conjugate pair, however neither would accept or donate an H+. All help is appreciated!