Question

in a ____ reaction, two elements or radicals change places with two other elements or radicals. answer options: select one of four double-replacement reversible combination decomposition

Explanation:

To solve this, we analyze each option:

• double - replacement: In a double - replacement reaction, the general form is \(AB + CD

ightarrow AD+CB\), where two elements or radicals (parts of compounds) switch places. This matches the description in the question.

• reversible: A reversible reaction is one that can proceed in both forward and reverse directions, and it does not describe the process of elements/radicals switching places.
• combination: A combination reaction is of the form \(A + B

ightarrow AB\), where substances combine to form a single product, not involving switching places.

• decomposition: A decomposition reaction is \(AB

ightarrow A + B\), where a compound breaks down into simpler substances, not involving switching places.

Answer:

A. double - replacement