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Flashcards in ISA Deck (16):
0

What is a homogeneous system?

A system in which all reactants are in the same state.

1

Why is it possible to titrate into an equilibrium without the equilibrium simply rebalancing?

Because the equilibrium reaction is much slower than the titration reaction.

2

What is the equilibrium constant, Kc?

The ratio of the concentrations of product to reactant, with each concentration to the power of the number of moles respective to it.

3

How does the equilibrium constant change with temperature?

For an endothermic reaction, the constant increases with temperature.
For an exothermic reaction, the constant decreases with temperature.

4

What are the units of Kc, the equilibrium constant?

Depends on the equilibrium.

5

What are are the units of the values used to calculate the equilibrium constant?

Mol/dm³

6

What does Le Chatelier's principle state?

That when a system at equilibrium is disturbed, the equilibrium position moves in the directions that will reduce the disturbance.

7

Do catalysts have any effect upon the value of the equilibrium constant? If not, why not?

No. They increase the rate of reaction for the forward reaction and the reverse reaction equally.

8

How does a catalyst work?

By reducing the activation energy necessary for a reaction.

9

What is the Bronsted-Lowry definition of an acid and a base?

An acid is a substance which can donate a proton and a base is a substance which can accept a proton.

10

What is the value of the ionic product of water?

1 x 10^(-14) (mol/dm³)

11

What is pH defined as?

-log[H⁺]

12

What is a weak acid?

An acid which only dissociates partially in aqueous solution.

13

What is a strong acid?

An acid which dissociates completely in aqueous solution.

14

What is Ka?

The acid dissociation constant. It is the ratio between the number concentration of the products and the reactants in the dissociation of the acid.

15

What is pKa?

-log(Ka)