Classify the following as chemical or physical changes.
boiling of water to form steam

Explanation

To classify the boiling of water to form steam as a chemical or physical change, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Process**: The process described is the boiling of water. When water is heated, it changes from a liquid state to a gaseous state (steam).

2. **Identify the Type of Change**: We need to determine whether this change involves a change in the chemical composition of the substance or just a change in its physical state.

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