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 element (metal or nonmetal)

Explanation

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

### Step 1: Identify the oxide formed
The question states that the element combines with oxygen to form an oxide. Let's denote the element as 'X'. The oxide can be represented as \( X + O_2 \rightarrow X_2O_n \) (where 'n' is the appropriate subscript based on the valency of the element).

### Step 2: Analyze the solubility of the oxide
It is given that this oxide dissolves in water. This means that when the oxide is added to water, it forms an aqueous solution.

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