Mcat: Gc Ch. 10

Front 1

What is an Arrhenius acid or base?

Back 1

acid: dissociates to form an excess of H in solution;

base: dissociate to form excess of OH in solution;

Front 2

What is a Bronsted-Lowry acid or base?

Back 2

acid: species that donates H ions;

base: a species that accepts them

---> not limited to solutions

Front 3

What is a Lewis acid or base? What's the mnemonic?

Back 3

acid: electron pair acceptor

base: electron pair donor;

Lewis Acid is an Acceptor of electron pairs;

Front 4

what is an amphoteric species? amphiprotic?

Back 4

one that reacts like an acid in a basic environment and like a base in an acidic environment;

amphiprotic: can either gain or lose a proton

Front 5

Upon what factors is Kw dependent?

Back 5

only temperature

Front 6

When is pH = 7 --> neutral valid?

Back 6

only at 25 degrees C

Front 7

What is a trick for calculating log values when it isn't 1 x 10^-m?

Back 7

long(n x 10^-m) = -log(n) - log(10^-m)

= m - log(n) -----? p = m - 0.n

Front 8

What is the equation for the acid dissociation constant?

Back 8

Ka = [H3O+][A-]/[HA];

the smaller the Ka, the weaker the acid;

generally, weak acid if Ka is less than 1.0, same for weak base

Front 9

What is induction?

Back 9

electronegative elements positioned near an acidic proton increase acid strength by pulling electron density out of the bond holding the acidic proton

Front 10

What happens when you react a strong acid with a weak base?

or opposite?

Back 10

(strong a) + (weak b) --> (very weak b) + (okay a);

(okay a) + (water) --> (weak b) + (H3O+);

final pH below 7

Front 11

what happens if you react a weak acid and a weak base?

Back 11

must compare the strengths of the reactants;

if one has a stronger Kb than the other has a Ka, then it will be more basic, etc.

Front 12

what is an acid equivalent?

Back 12

1 mole of H

Front 13

What is normality?

Back 13

quantity of acidic or basic capacity;

so each mole of H3PO4 yields three moles of H3O. so 3N

Front 14

What is gram equivalent weight?

Back 14

mass of a compound that produces one equivalent (one mole of H or OH)

Front 15

what is a titrant?

Back 15

the solution of known concentration

Front 16

what is the equivalence point? what is the equation that represents this?

Back 16

when number of acid equivalents present in the original solution equals number of base equivalents, vice-versa;

NaVa = NbVb

Front 17

What are the three most population buffer systems?

Back 17

acetic acid (CH3COOH) and sodium acetate (CH3COO-Na+);

ammonia (NH3) and ammonium chloride (NH4+Cl-);

Bicarbonate CO2 (g) + H2O (l) <--> H2CO3 <--> H+ +HCO3-

Front 18

What is the range of optimal activity for buffers?

Back 18

pKa +/- 1

Front 19

What is the Henderson-Hasselbalch equation? both pKa and pKb forms

Back 19

pH = pKa + log [A-]/[HA];

pOH = pKb + log [B+]/[BOH]