Kc/Acids stuff Definitons

Question 1

The equilibrium law states that?

Answer 1

The equilibrium law states that for the equilibrium

aA + bB cC + dD

Kc = [C]^c[D]^d/[A]^a[B]^b

Question 2

What is a dynamic equilibrium?

Answer 2

A dynamic equilibrium exists in a closed system when the rate of the forward reaction is equal to the rate of the reverse reaction.

Question 3

What is a homogeneous equilibrium?

Answer 3

A homogeneous equilibrium is an equilibrium in which all the species making up the reactants and products are in the same physical state.

Question 4

What is a heterogeneous equilibrium?

Answer 4

An equilibrium in which species making up the reactants and products are in different physical states.

Question 5

What is a Bronsted-Lowry acid?

Answer 5

A Bronsted-Lowry acid is a proton, H+, donor.

Question 6

What is a Bronsted-Lowry base?

Answer 6

A Bronsted-Lowry base is a proton, H+, acceptor.

Question 7

What is an alkali?

Answer 7

An alkali is a base that dissolves in water forming OH-(aq) ions.

Question 8

Neutralisation

Answer 8

Neutralisation is a chemical reaction in which an acid and a base react together to produce a salt and water.

Question 9

An acid-base pair

Answer 9

An acid-base pair is a pair of two species that transform into each other by gain or loss of a proton.

Question 10

pH?

Answer 10

pH = -log[H*(aq)]

Question 11

A strong acid

Answer 11

A strong acid is an acid that completely dissociates in solution.

Question 12

A weak acid

Answer 12

A weak acid is an acid that partially dissociates in solution.

Question 13

The acid dissociation constant, Ka.

Answer 13

The acid dissociation constant, Ka, of an acid HA is defined as…

Ka = [H*(aq)][A-(aq)]/[HA(aq)

Question 14

pKa?

Answer 14

pKa = -log Ka

Question 15

The ionic product of water, Kw, is defined as?

Answer 15

Kw = [H*(aq)][OH-(aq)]

At 25*C, Kw = 1.00 x 10^-14 mol^2 dm^-6

Question 16

A buffer solution

Answer 16

A buffer solution is a mixture that minimises pH changes

on addition of small amounts of acid or base.

Question 17

The equivalence point

Answer 17

The equivalence point is the point in a titration at which the volume of one solution has reacted exactly with the volume of a second solution.

Question 18

The end point

Answer 18

The end point is the point in a titration at which there are equal concentrations of the weak acid and conjugate base forms of the indicator.

The colour at the end point is midway between the colours of the acid and conjugate base forms.

Question 19

The standard enthalpy change of neutralisation

Answer 19

The standard enthalpy change of neutralisation is the energy change that accompanies the neutralisation of an aqueous acid by an aqueous base to form one mole of H2O(l) under standard conditions.