Which of the given statements for mercury cell are incorrect? (i)Mercury cell is suitable for low current devices like hearing aids, watches, etc. (ii)It consists of zinc-mercury amalgam as anode and a paste of HgO and carbon as the cathode. (iii)The electrolyte is a paste of `Zn(OH)_2` and `KO_2`. (iv)The electrolyte reactions for the cell are At anode : `Zn(Hg)+ H_2O to ZnO_((s)) + 2OH^(-) + 2e^(-)` At cathode : `HgO + H_2O + 2e^(-) to Hg_((l)) + 2OH^-`A. (ii) and (iii) onlyB. (i) and (ii) onlyC. (i),(iii) and (iv) onlyD. (iii) and (iv) only

Which of the given statements for mercury cell are incorrect? (i)Merc

1.	Which of the given statements for mercury cell are incorrect? (i)Mercury cell is suitable for low current devices like hearing aids, watches, etc. (ii)It consists of zinc-mercury amalgam as anode and a paste of HgO and carbon as the cathode. (iii)The electrolyte is a paste of `Zn(OH)_2` and `KO_2`. (iv)The electrolyte reactions for the cell are At anode : `Zn(Hg)+ H_2O to ZnO_((s)) + 2OH^(-) + 2e^(-)` At cathode : `HgO + H_2O + 2e^(-) to Hg_((l)) + 2OH^-`A. (ii) and (iii) onlyB. (i) and (ii) onlyC. (i),(iii) and (iv) onlyD. (iii) and (iv) only
Answer» Correct Answer - D The electrolyte in a mercury cell is a paste of KOH and ZnO. The electrode reactions for the cell are `{:("At anode",Zn(Hg)+2OH^(-) to ZnO_((s))+H_2O+2e^(-)),("At cathode",HgO+H_2O + 2e^(-) to Hg_((l))+2OH^(-)):}`

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Define molar conductivity of a solution and explain how molar conductivity changes with change in concentration of a solution for a weak and a strong electrolyte.
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What are elementary reactions ?

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