a current of 4.5A is passed through a solution of gold salt for 1hr 45mins.
calculate (i)the mass of gold deposited
(ii)the number of mole of gold deposited
Au salts are +1 or +3. I will assume the problem means Au^3+
coulombs = amperes x seconds
C = 4.5 A x 1.75 hours x (60 min/hr) x (60 sec/min) = 28,350
96,485 C will deposit 197/3 or 65.67 grams Au.
So the amount to be deposited will be 65.67 g x (28,350/96,485) = ? g Au
mols Au = grams Au/197