Which of the following is not a physical property?

Options

A. specific heat
B. melting point
C. reaction with other elements or com pounds
D. freezing point

Explanation

To determine which of the following is not a physical property, we need to first understand the definitions of physical and chemical properties.

### Step-by-Step Solution:

1. **Define Physical Properties**: Physical properties are characteristics of a substance that can be observed or measured without changing the substance's chemical identity. Examples include color, density, melting point, boiling point, and specific heat.

2. **Define Chemical Properties**: Chemical properties describe a substance's potential to undergo chemical changes or reactions. These properties can only be observed during a chemical reaction and include reactivity with other chemicals, flammability, and acidity.

3. **Analyze the Options**:
- If the options include properties like specific heat, melting point, and freezing point, these are all measurable and describe the physical state of the substance, thus they are physical properties.
- If one of the options describes a reaction with other elements or compounds, this indicates a change in chemical identity, which means it is a chemical property.

4. **Identify the Correct Answer**: Based on the definitions and analysis, the option that describes a reaction with other elements or compounds is the one that is not a physical property. This option is the correct answer.

### Conclusion:
The property that is not a physical property is the one that involves a reaction with other elements or compounds.

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