A student designs an ammeter (a device that measures electrical current) that is based on the electrolysis of water into hydrogen and oxygen gases. When electrical current of unknown magnitude is run through the device for 1.00 min , 15.4 mL of water-saturated H2(g) is collected. The temperature and pressure of the system are 25 ∘C and 715 torr.

Answer 1

Use PV=nRT to find n, the moles of hydrogen gas.

V= 1.68x10^-2 L
P= 715 torr-VP of water at 25C (about 25 torr; look it up in Wikipedia)
T= 298.2K
R = Applicable value for the above units.