Chapter 18, Problem 20A

Interpretation Introduction

Interpretation: The element that is oxidized and reduced to be identified from given reaction.

$2\text{AgBr}\left(s\right)\to 2\text{Ag}\left(s\right)+{\text{Br}}_{\text{2}}\left(g\right)$

Concept introduction: Oxidation state is the charge assigned to an atom in a compound. Oxidation-reduction reaction involves gain and loss of electrons from atoms.

Answer to Problem 20A

Bromine is oxidized and silver is reduced.

Explanation of Solution

The given reaction is as follows:

$2\text{AgBr}\left(s\right)\to 2\text{Ag}\left(s\right)+{\text{Br}}_{\text{2}}\left(g\right)$

For above reaction, bromine is oxidized because oxidation state of bromine increases from -1 to 0. Silver (Ag) is reduced because oxidation state of Ag decreases from +1 to 0.

Conclusion

Oxidation − reduction reaction is a chemical reaction which associates transfer of electrons.