What will happen when .
magnesium oxide is tested with blue litmus paper?

Explanation

To determine what happens when magnesium oxide is tested with blue litmus paper, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Nature of Litmus Paper**:
- Litmus paper is a pH indicator used to determine whether a solution is acidic or basic. Blue litmus paper turns red in acidic solutions and remains blue in basic solutions.

2. **Identify Magnesium Oxide**:
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