Redox Reactions And Electrochemistry Ques 562
Question: An electrochemical cell is set up as: $ Pt;H_2(1,atm)|HCl(0.1M)||CH_3COOH(0.1M)|H_2 $ (1atm); Pt. The e.m.f of this cell will not be zero, because
Options:
A) the temperature is constant
B) e.m.f depends on molarities of acids used
C) acids used in two compartments are different
D) pH of $ 0.1MHCl $ and $ 0.1,M,CH_3COOH $ is not same
Show Answer
Answer:
Correct Answer: D
Solution:
[d] For a concentration cell having different concentrations of ions. $ E=-\frac{0.0591}{n}\log \frac{c_1}{c_2} $ If all the concentrations are identical then obviously the cell voltage is zero. But as the pH of 0.1 M $ HCl $ (strong acid) and pH of 0.1 M $ CH_3COOH $ is (weak acid) not same, therefore the cell voltage is not zero.
