Advertisements
Advertisements
प्रश्न
A current of 1.608A is passed through 250 mL of 0.5 M solution of copper sulphate for 50 minutes. Calculate the strength of Cu2+ after electrolysis assuming volume to be constant and the current efficiency is 100%.
उत्तर
Given I = 1.608A
t = 50 min = 50 × 60 = 3000 S
V = 250 mL
C = 0.5M
η = 100%
Calculate the number of Faradays of electricity passed through the CuSO4 solution
Q = It
Q = 1.608 × 3000
Q = 4824 C
∴ Number of Faradays of electicity = `(4824 "C")/(96500 "C")` = 0.05F
Electrolysis of CuSO4
\[\ce{Cu^{2+}_{( aq)} + 2e^- -> Cu_{(s)}}\]
The above equation shows that 2F electricity will deposit 1 mole of Cu2+ to Cu.
∴ 0.05F electricity will deposit
`(1 "mol")/(2"F") xx 0.05 "F"` = 0.025 mol
Initial number of molar of Cu2+ in 250 ml of solution
= `0.5/(1000 "mL") xx 250 "mL"`
= 0.125 mol
∴ Number of moles of Cu2+ after electrolysis
= 0.125 − 0.025
= 0.1 mol
∴ Concentration of Cu2+
= `(0.1 "mol")/(250 "mL") xx 1000 "mL"`
= 0.4 M
APPEARS IN
संबंधित प्रश्न
Consider the following half cell reactions:
\[\ce{Mn^{2+} + 2e^- -> Mn}\] E0 = –1.18 V
\[\ce{Mn^{2+} -> Mn^{2+} + e^-}\] E0 = –1.51 V
The E0 for the reaction \[\ce{3Mn^{2+} -> Mn + 2Mn^{3+}}\], and the possibility of the forward reaction are respectively.
During electrolysis of molten sodium chloride, the time required to produce 0.1 mole of chlorine gas using a current of 3A is ___________.
While charging lead storage battery
Among the following cells
I) Leclanche cell
II) Nickel – Cadmium cell
III) Lead storage battery
IV) Mercury cell
Primary cells are:
In \[\ce{H2 - O2}\] fuel cell the reaction occurs at cathode is:
State Faraday’s Laws of electrolysis.
Calculate the standard emf of the cell: \[\ce{Cd|Cd^{2+}||Cu^{2+}|Cu}\] and determine the cell reaction. The standard reduction potentials of Cu2+|Cu and Cd2+|Cd are 0.34 V and −0.40 volts respectively. Predict the feasibility of the cell reaction.
8.2 × 1012 litres of water is available in a lake. A power reactor using the electrolysis of water in the lake produces electricity at the rate of 2 × 106 Cs−1 at an appropriate voltage. How many years would it like to completely electrolyse the water in the lake? Assume that there is no loss of water except due to electrolysis.
Derive an expression for the Nernst equation.
Explain the function of H2 – O2 fuel cell.
