Advertisements
Advertisements
Question
A solution of Ni(NO3)2 is electrolysed between platinum electrodes using a current of 5 amperes for 20 minutes. What mass of Ni is deposited at the cathode?
Advertisements
Solution
The reaction takes place in the following manner:
\[\ce{Ni^{2+} + 2e- -> Ni}\]
Atomic weight of \[\ce{Ni}\] = 58.70
Equivalent weight of Ni = \[\ce{\frac{Atomic weight}{Number of valence electrons}}\]
= \[\ce{\frac{58.70}{2}}\]
= 29.35
According to Faraday’s first law of electrolysis,
\[\ce{W = Z . I . t = \frac{Equivalent weight}{96500} \times I \times t}\]
= \[\ce{\frac{29.35}{96500} × 5 \times 20 \times 60}\]
= 1.825 g
APPEARS IN
RELATED QUESTIONS
Write any four applications of electrochemical series
Three electrolytic cells A, B, C containing solutions of ZnSO4, AgNO3 and CuSO4, respectively, are connected in series. A steady current of 1.5 amperes was passed through them until 1.45 g of silver deposited at the cathode of cell B. How long did the current flow? What mass of copper and zinc were deposited?
Draw neat labelled diagram of electrolytic refining of blister copper
What is the ratio of volumes of H2 and O2 liberated during electrolysis of acidified water?
(A) 1 : 2
(B) 2 : 1
(C) 1 : 8
(D) 8 : 1
State second law of electrolysis
Explain Faraday’s second law of electrolysis
Following reactions occur at cathode during the electrolysis of aqueous copper(II) chloride solution :
On the basis of their standard reduction electrode potential (E°) values, which reaction is feasible at the cathode and why ?
Solve the following question.
A steady current of 2 amperes was passed through two electrolytic cells X and Y connected in series containing electrolytes FeSO4 and ZnSO4 until 2.8 g of Fe deposited at the cathode of cell X. How long did the current flow? Calculate the mass of Zn deposited at the cathode of cell Y.
(Molar mass : Fe = 56 g mol–1, Zn = 65.3 g mol–1, 1F = 96500 C mol–1)
Electrolytic cell uses electrical energy to bring about ____________.
According to Faraday’s First Law of Electrolysis, the amount of chemical reaction which occurs at any electrode during electrolysis by a current is proportional to the ____________.
In the electrolysis of aqueous sodium chloride solution which of the half cell reaction will occur at anode?
Aqueous copper sulphate solution and aqueous silver nitrate solution are electrolysed by 1 ampere current for 10 minutes in separate electrolytic cells. Will the mass of copper and silver deposited on the cathode be same or different? Explain your answer.
Consider the figure and answer the following question.
Cell ‘A’ has ECell = 2V and Cell ‘B’ has ECell = 1.1V which of the two cells ‘A’ or ‘B’ will act as an electrolytic cell. Which electrode reactions will occur in this cell?
When during electrolysis of a solution of AgNO3, 9650 coulombs of charge pass through the electroplating bath, the mass of silver deposited on the cathode will be ______.
Through an aqueous solution of an unknown salt of metal M (M = 200 g/mol) a current of 1.93 A is passed for 50 min. If 4 g of metal is produced at cathode. The charge on metal ion in solution is ______.
A current of 4 amp was passed for 2 hours through a solution of copper sulphate when 5.0 g of copper was deposited. The current efficiency is ______% (Cu = 63.5).
Assertion (A): During electrolysis of aqueous copper sulphate solution using copper electrodes hydrogen gas is released at the cathode.
Reason (R): The electrode potential of Cu2+/Cu is greater than that of H+/H2.
Select the most appropriate answer from the options given below:
How much electricity in terms of Faraday is required to produce 40.0 g of Al from molten Al2O3?
(Given: Molar mass of Aluminium is 27 g mol−1.)
