Answer: 4 molL-1
Explanation:
Detailed solution is shown in the image attached. The number of moles of NaCl is first obtained. Since the molarity must be in units of molL-1, the volume is divided by 1000 and the formula stated in the solution is applied and the answer is given to one significant figure.
Answer: 530 hours
Explanation:
The reduction of Nickel ions to nickel is shown as:
of electricity deposits 1 mole of Nickel
1 mole of Nickel weighs = 58.7 g
Given quantity = 18.0 kg = 18000 g (1kg=1000g)
58.7 g of Nickel is deposited by 193000 C of electricity
18000 g of Nickel is deposited by = of electricity
where Q= quantity of electricity in coloumbs = 59182282.8C
I = current in amperes = 31.0 A
t= time in seconds = ?
(1h=3600 sec)
Thus 530 hours are required to plate 18.0 kg of nickel onto the cathode if the current passed through the cell is held constant at 31.0 A