Question

Compound(s) of $Cu$ and $Ag$ showing $+3$ oxidation state is\are :

• A. $K_3\left[Cu{F}_6\right]$
• B. $Na\left[Ag{F}_4\right]]$
• C. both a and b
• D. none of these

Answer 1

The correct option is C both a and b

Compound of $Cu$ and $Ag$ showing $+3$ oxidation state are $K_3\left[Cu{F}_6\right]$ and $Na\left[Ag{F}_4\right]$.
Let $x$ be the oxidation number of $Cu$ in $K_3\left[Cu{F}_6\right]$.
Since the overall charge on the compound is $0$, the sum of oxidation states of all elements in it should be equal to $0$.
Therefore, $3(+1)+x+6(-1)=0$
or, $x=-3$
Let $y$ be the oxidation number of Ag in $Na\left[Ag{F}_4\right]$.
Since the overall charge on the compound is $0$, the sum of oxidation states of all elements in it should be equal to $0$.
Therefore, $+1+y+4(-1)=0$
or, $y=+3$