Chapter 17, Problem 98QAP

Which of the changes below will increase the voltage of the following cell?
$\text{Co}|{\text{Co}}^{2+}\left(0.010M\right)\Vert {\text{H}}^{+}\left(0.010M\right)|{\text{H}}_2\left(0.500\text{atm}\right)|\text{Pt}$
(a) Increase the volume of COCl₂ solution from 100 mL to 300 mL.
(b) Increase [H⁺] from 0.010 M to 0.500 M.
(c) Increase the pressure of H₂ from 0.500 atm to 1 atm.
(d) Increase the mass of the Co electrode from 15 g to 25 g.
(e) Increase [CO²⁺] from 0.010 M to 0.500 M.