Rate = change in concentration/ change in time. [A] is shorthand for ‘concentration of A’. Rate of Reaction: The change in concentration of a reactant or product per unit time. Units: Usually it is mol dm-3 s-1. -1 in superscript means ‘per’ or ‘divide’. Orders...

# Rates of Reactions

## Concentration- Time Graphs

Colorimeter: Monitoring colour change/ concentration. Amount of light absorbed by solution. Experiment Method: Prepare standard solutions of known concentrations of solution. Choose filter with complementary colour to coloured chemical. Zero colorimeter with water....

## Rate- Concentration Graphs

Rate- Concentration Graphs: Zero Order: Straight horizontal line with zero gradient. Rate = k[A]0 so rate = k = Y intercept. Reaction rate does not change with concentration. Can confirm first order of reaction of graph by calculating two half-lives and constant....

## Rate- Determining Step

Reaction Mechanism: Reactions take place in series of steps called reaction mechanism. - Collision unlikely between more than 2 species in one step. - Also stoichiometry in rate equation may not match overall equation. Rate- Determining Step: The steps in reactions...

## Rate Constants and Temperature

Temperature Increase: As temperature increases, rate increases and the value of rate constant k increases. This is due to two factors… Kinetic Energy: As temperature increases, particles move faster and collide more frequently. Activation Energy: Increasing...