Lecturer 1

Question 1

What is Arrhenius’ equation

Answer 1

k = Ae ^ (-Ea/RT)

Question 2

How does the rate law of elementary reactions differ from ordinary net reactions?

Answer 2

• rate law can be written by inspection of stoich

- for ordinary ones, must be determined experimentally

Question 3

What is the rate determining step?

Answer 3

The slow step

- the overall reaction cannot occur faster than the slowest step in reaction sequence

Question 4

What do you do when the RDS cannot be easily determined?

Answer 4

use steady state approximation

Question 5

What is the steady state approximation?

Answer 5

• the concentration of the intermediate remains constant during the reaction
• rate of production = rate of consumption

Question 6

What are the 2 forms of energy?

Answer 6

Potential - energy stores or ready to be released

Kinetic - moving objects have energy of motion

Question 7

How are system, surroundings and universe related?

Answer 7

• System - the thing of interest
• Surroundings - everything else
• Universe = system + surroundings

Question 8

What is internal energy?

Answer 8

The sum of energies of all individual particles in a sample of matter (U)

Question 9

Enthalpy

Answer 9

Function related to the heat absorbed or evolved by a chemical system (H)

Question 10

Entropy

Answer 10

A measure of the number of ways energy is distributed throughout a chemical system
(S)

Question 11

Gibbs energy

Answer 11

(G)
• the energy that is available to do work
• G = H - TS