Rates of Reaction

Introduction to Measuring Rate of Reaction

• Rate of reaction is a measure of how quickly a chemical reaction takes place.
• It is important to be able to measure the rate of a reaction accurately to understand the factors that affect the rate.

Methods of Measuring Rate

1. Measuring the mass or volume of products

• The mass or volume of products formed can be measured over time to calculate the rate of reaction.
• This is commonly used for reactions where a gas is produced, such as the reaction between hydrochloric acid and marble chips.

2. Measuring the disappearance of reactants

• The mass or concentration of reactants can be measured over time to calculate the rate of reaction.
• This is commonly used for reactions where a colored reactant is consumed, such as the reaction between sodium thiosulfate and hydrochloric acid.

3. Measuring the change in temperature

• The change in temperature over time can be used to calculate the rate of an exothermic reaction.
• This is commonly used for reactions where a lot of energy is released, such as the reaction between sulfuric acid and sodium hydroxide.

Factors Affecting Rate of Reaction

• Concentration of reactants
• Temperature
• Pressure (for gaseous reactions)
• Presence of a catalyst