Question

Which molecules represents the unerlined atoms in their lowest oxidation state?

• A. $F_2\underset{–}{O}$
• B. $H_2\underset{–}{S}$
• C. $\underset{–}{P}{H}_3$
• D. ${\underset{–}{N}}_2{H}_4$

Answer 1

Answer: (B), (C)

$H_2\underset{–}{S}$
$\underset{–}{P}{H}_3$

$H_2\underset{–}{S}$ and $\underset{–}{P}{H}_3$ represents the unerlined atoms in their lowest oxidation state.
The oxidation state of S in $H_2\underset{–}{S}$ is -2 and the oxidation state of P in $\underset{–}{P}{H}_3$ is -3.