Fill in the blanks to make true statements.
When electric current is passed through water containing a small amount of dilute sulphuric acid, then
--(chemical physical) reaction takes place.

Explanation

To fill in the blank in the statement, we need to analyze the situation described:

1. **Understanding the context**: The statement is about passing electric current through water that contains a small amount of dilute sulphuric acid.

2. **Identifying the type of reaction**: When electric current is passed through this solution, it leads to the breakdown of water into its constituent elements, hydrogen and oxygen. This process is known as electrolysis.

3. **Determining the nature of the reaction**: The breakdown of water into hydrogen and oxygen is a chemical change because it involves the formation of new substances (hydrogen and oxygen gases) from water (H2O).

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