Question

Among the following, what is the total number of compounds having +3 oxidation state of the underlined elements?
a. $K_4\underset{–}{P_2}{O}_7$
b. $Na\underset{–}{Au}{Cl}_4$
c. ${Rb}_{4}Na\left[H\underset{–}{V_{10}}{O}_{28}\right]$
d. $\underset{–}{I}Cl$
e. ${Ba}_2\underset{–}{Xe}{O}_6$
f. $\underset{–}{O}{F}_2$
g. $Ca{\left(\underset{–}{Cl}{O}_2\right)}_2$
h. $\underset{–}{N}{O}_2^{\ominus }$

Answer 1

The total number of compounds having $+3$ oxidation state of the underlined elements is $3$.
The $+3$ oxidation state of the underlined element is in (b) $Na\underset{–}{Au}{Cl}_4$, (g)$Ca{\left(\underset{–}{Cl}{O}_2\right)}_2$, and (h)$\underset{–}{N}{O}_2^{\ominus }$.
The compounds and the oxidation states of the underlined elements are shown below:
a. $K_4\underset{–}{P_2}{O}_7$ $+5$
b. $Na\underset{–}{Au}{Cl}_4$ $+3$
c. ${Rb}_{4}Na\left[H\underset{–}{V_{10}}{O}_{28}\right]$ $+5$
d. $\underset{–}{I}Cl$ $+1$
e. ${Ba}_2\underset{–}{Xe}{O}_6$ $+8$
f. $\underset{–}{O}{F}_2$ $+2$
g. $Ca{\left(\underset{–}{Cl}{O}_2\right)}_2$ $+3$
h. $\underset{–}{N}{O}_2^{\ominus }$ $+3$