The rate of chemical change is directly proportional to …………… .

Explanation

To solve the question "The rate of chemical change is directly proportional to ……………", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Rate of Reaction**:
The rate of a chemical reaction refers to how quickly reactants are converted into products. It is influenced by various factors, including the concentration of reactants.

2. **Proportionality to Concentration**:
The rate of a chemical reaction is directly proportional to the concentration of the reactants involved in the reaction. This means that as the concentration of the reactants increases, the rate of the reaction also increases.

3. **Order of Reaction**:
The relationship between the rate of reaction and the concentration of reactants can be expressed mathematically. If we consider a general reaction:
\[ A + B \rightarrow \text{Products} \]
The rate of the reaction can be expressed as:
\[ \text{Rate} = k [A]^m [B]^n \]
where:
- \( k \) is the rate constant,
- \( [A] \) and \( [B] \) are the concentrations of reactants A and B,
- \( m \) and \( n \) are the orders of the reaction with respect to A and B, respectively.

4. **Conclusion**:
From the above expression, we can conclude that the rate of chemical change is directly proportional to the concentration of the reactants raised to their respective orders.

### Final Answer:
The rate of chemical change is directly proportional to the concentration of the reactants raised to their respective orders.

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