Question

Which element can exhibit more than one oxidation state in compounds?
1. $Cr$
2. $Pb$
3. $Sr$

• A. $1$ only
• B. $1$ and $2$ only
• C. $2$ and $3$ only
• D. $1,2$ and $3$

Answer 1

Answer: (B)

$1$ and $2$ only

Chromium exhibits a variety of oxidation states because its valence electrons are in the d orbital.
$Pb$ has more than one oxidation state as well . It exhibits $P{b}^{2+}andP{b}^{4+}$.
Strontium is an alkali earth metal and it is highly electropositive. It exhibits only $S{r}^{2+}$.
Hence option B is the right answer.