An element combines with oxygen to form an oxide. This oxide dissolves in water. This aqueous solution changes blue litmus to red. Write
the nature of the aqueous solution (alkaline or acidic).

Explanation

To determine the nature of the aqueous solution formed when an element combines with oxygen to form an oxide, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reaction**: The element combines with oxygen to form an oxide. This means we have an oxide of the element, which can be either acidic, basic, or amphoteric depending on the element.

2. **Dissolution in Water**: The oxide dissolves in water. When oxides dissolve in water, they can form either acidic or basic solutions.

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