Unit 1 - Rate of Reaction

Reversible Reaction

A reaction where products can reform reactants

Gas Volume Measurement

Measures the volume of gas produced over time using a gas syringe apparatus

Instantaneous Rate

Found by drawing a tangent to the curve at a specific time and calculating its gradient

Effect of Pressure

Increasing pressure in gaseous reactions increases concentration

Mean Rate Calculation

Calculated using data from any two points on a concentration-time graph: $\frac{\text{Change in concentration}}{\text{Change in time}}$

Effect of Concentration

Increasing concentration means more particles in the same volume

Effect of Temperature Change on Equilibrium

Increasing temperature favors the endothermic direction

Mass Loss Method

Measures loss in mass as gas is produced during a reaction

Factors Affecting Reaction Rate

Temperature

Effect of Concentration Change on Equilibrium

Increasing reactant concentration or decreasing product concentration shifts the equilibrium towards producing more products

Units of Reaction Rate

g/s

Activation Energy

The minimum energy required for particles to collide successfully and initiate a reaction

Effect of Temperature

Increasing temperature gives particles more energy

Effect of Surface Area

Smaller pieces of a substance have a larger surface area to volume ratio

Cross Disappearance Method

Measures the time taken for a cross to disappear as a reaction produces a cloudy precipitate

Collision Theory

Chemical reactions occur when particles collide with sufficient energy to overcome the activation energy barrier

Dynamic Equilibrium

A state where forward and reverse reactions occur at the same rate in a closed system

Rate Formula

$\frac{\text{Amount of reactant used}}{\text{Time}}$ or $\frac{\text{Amount of product formed}}{\text{Time}}$

Rate of Chemical Reaction

Measures how quickly reactants are consumed or products are formed over time

Effect of Pressure Change on Equilibrium

Increasing pressure shifts the equilibrium towards the side with fewer gas molecules

Catalyst

A substance that provides an alternative reaction pathway with lower activation energy

Le Chatelier's Principle

If a system at equilibrium is disturbed