Theory of 'active mass' indicates that the rate of a chemical reaction is directly proportional to the

Options

A. Equilibrium constant
B. Properties of reactants
C. Volume of apparents
D. Concentration of reactants

Answer

To solve the question regarding the theory of 'active mass' and its relation to the rate of a chemical reaction, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Active Mass**:
The term 'active mass' refers to the effective concentration of reactants in a chemical reaction. It is a measure of the amount of a substance that is available to react.

2. **Rate of Reaction**:
According to the theory of active mass, the rate of a chemical reaction is influenced by the concentrations of the reactants involved in the reaction.

3. **Proportionality**:
The theory states that the rate of a reaction is directly proportional to the product of the active masses (concentrations) of the reactants. This means that if the concentration of the reactants increases, the rate of the reaction also increases.

4. **Rate Law Expression**:
For a general reaction \( A + B \rightarrow \text{Products} \), the rate law can be expressed as:
\[ \text{Rate} = k[A]^m[B]^n \]
where \( k \) is the rate constant, and \( m \) and \( n \) are the orders of the reaction with respect to reactants \( A \) and \( B \), respectively.

5. **Conclusion**:
Therefore, according to the theory of active mass, the rate of a chemical reaction is directly proportional to the concentration of the reactants.

### Final Answer:
The rate of a chemical reaction is directly proportional to the concentration of the reactants.

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