Classify the following as chemical or physical changes.
dissolving common salt in water

Explanation

To classify the process of dissolving common salt in water as a chemical or physical change, we can follow these steps:

### Step 1: Understand the Definitions
- **Physical Change**: A change that does not alter the chemical composition of a substance. The substance may change its state or appearance but can be reverted back to its original form.
- **Chemical Change**: A change that results in the formation of new chemical substances. This change is usually irreversible under normal conditions.

### Step 2: Analyze the Process
- When common salt (sodium chloride) is dissolved in water, it dissociates into its constituent ions (sodium ions and chloride ions). However, the chemical composition of the salt remains unchanged.
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