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%.
Advertisements
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.
The button cell used in watches functions as follows.
\[\ce{Zn_{(s)} + Ag2O_{(s)} + H2O_{(l)} ⇌ 2Ag_{(s)} + Zn^{2+}_{( aq)} + 2OH^-_{( aq)}}\] the half cell potentials are \[\ce{Ag2O_{(s)} + H2O_{(l)} + 2e^- -> 2Ag_{(s)} + 2OH^-_{( aq)}}\] E0 = 0.34 V The cell potential will be
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:
For the cell reaction
\[\ce{2Fe^{3+}_{( aq)} + 2l^-_{( aq)} -> 2Fe^{2+}_{( aq)} + l2_{( aq)}}\]
\[\ce{E^0_{cell}}\] = at 298 K. The standard Gibbs energy (∆G°) of the cell reactions 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.
Explain the function of H2 – O2 fuel cell.
