In ______ reaction, two compounds in their aqueous state exchange their positive and negative radicals mutually to form two new compounds. [Direct combination/double decomposition]

Explanation

To solve the question, we need to identify the type of reaction being described. The question states that two compounds in their aqueous state exchange their positive and negative radicals mutually to form two new compounds.

### Step-by-Step Solution:

1. **Understanding the Reaction**: The question describes a reaction where two compounds exchange their ions. This is a key characteristic of certain types of chemical reactions.

2. **Identifying the Type of Reaction**: The reaction involves the mutual exchange of positive and negative ions (or radicals). This is indicative of a specific type of reaction known as a double displacement reaction.

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