Question

The value of the reaction quotient $Q$ for the cell
$Z ( s )\left| Zn ^{2+}(0.01 M )\right|\left| Ag ^{\oplus}(1.25 \,M )\right| Ag ( s )$ is

• A. 156
• B. 125
• C. $1.25 \times 10^{-2}$
• D. $64 \times 10^{-3}$

Answer 1

Answer: (D)

Write cell reaction:
$ Zn ( s )+2 Ag ^{\oplus}(1.25 M ) \rightarrow Zn ^{2+}(0.01 M )+2 Ag ( s ) $
$Q=\frac{\left[ Zn ^{2+}\right]}{\left[ Ag ^{\oplus}\right]}=\frac{0.01}{(1.25)^2}=64 \times 10^{-3}$