Question

If a Zn2+/Zn electrode is diluted 100 times, then the emf will show:

• A. (A) An increase of 59 mV
• B. (B) A decrease of 59 mV
• C. (C) An increase of 29.5 mV
• D. (D) A decrease of 29.5 mV

Answer 1

Answer: (B)

(B) A decrease of 59 mV

Answer 2

Explanation:
We know,Ecell=0.0592log⁡1Cwhere, C=100 timesEcell =−0.0592log⁡1100 (∵log⁡1100=−2)=−0.0592×−2=0.059V=59 mVThus, if the Zn2+/Zn electrode is diluted to 100 times than the emf is decrease of 59 mV.Hence, the correct option is (B).