Question

$A{g}^{+}+N{H}_3\rightleftharpoons Ag(N{H}_3{)}^{+}$; $K_1=3.5\times {10}^{-3}$
$Ag\left(N{H}_3\right)+N{H}_3\rightleftharpoons \left[Ag\right(N{H}_3{)}_2]$; $K_2=1.7\times {10}^{-3}$
Then, the formation constant of $\left[Ag\right(N{H}_3{)}_2{]}^{+}$ from $A{g}^{+}$ and $N{H}_3$ is:

• A. $1.7\times {10}^{-3}$
• B. $5.92\times {10}^{-6}$
• C. $1.8\times {10}^3$
• D. $1.7\times {10}^7$

Answer 1

The correct option is B $5.92\times {10}^{-6}$

To get the formation constant add both reactions-

So the resultant $K=K_1\times K_2=3.5\times 1.7\times {10}^{-3}=5.95\times {10}^{-6}$