Rate of a Chemical Reaction
### Introduction
The rate of a chemical reaction is the change in concentration of reactants or products per unit time.
It is expressed as:
Rate = - (delta [Reactant] / delta t) = (delta [Product] / delta t)
where [ ] denotes concentration and t represents time.
### Factors Affecting Reaction Rate
1. **Concentration of Reactants**: Higher concentration increases collision frequency, speeding up
the reaction.
2. **Temperature**: Increasing temperature provides more energy to molecules, leading to faster
reactions.
3. **Nature of Reactants**: Ionic reactions occur faster than covalent reactions due to differences in
bond strengths.
4. **Catalysts**: Catalysts lower activation energy, increasing reaction speed without being
consumed.
5. **Surface Area**: Finely divided solids react faster due to increased surface exposure.
6. **Pressure (for gases)**: Higher pressure increases the concentration of gaseous reactants,
accelerating the reaction.
### Rate Law and Order of Reaction
The rate law expresses the relationship between reaction rate and reactant concentrations:
Rate = k [A]^m [B]^n
where k is the rate constant, m and n are reaction orders, and A & B are reactants.
### Introduction
The rate of a chemical reaction is the change in concentration of reactants or products per unit time.
It is expressed as:
Rate = - (delta [Reactant] / delta t) = (delta [Product] / delta t)
where [ ] denotes concentration and t represents time.
### Factors Affecting Reaction Rate
1. **Concentration of Reactants**: Higher concentration increases collision frequency, speeding up
the reaction.
2. **Temperature**: Increasing temperature provides more energy to molecules, leading to faster
reactions.
3. **Nature of Reactants**: Ionic reactions occur faster than covalent reactions due to differences in
bond strengths.
4. **Catalysts**: Catalysts lower activation energy, increasing reaction speed without being
consumed.
5. **Surface Area**: Finely divided solids react faster due to increased surface exposure.
6. **Pressure (for gases)**: Higher pressure increases the concentration of gaseous reactants,
accelerating the reaction.
### Rate Law and Order of Reaction
The rate law expresses the relationship between reaction rate and reactant concentrations:
Rate = k [A]^m [B]^n
where k is the rate constant, m and n are reaction orders, and A & B are reactants.
