Electrolytes and Electrolysis - MCQ - Advance Level

Electrolytes and Electrolysis-MCQ-Advance Level

Dear Readers,

Compared to other sections, Chemistry is considered to be the most scoring se
ction. If prepared thoroughly, chemistry can help students to secure a meritorious position in the exam. These questions are very important in achieving your success in Exams after 12th.

Q1. Which of the following aqueous solutions remains acidic after electrolysis?

•  K₂Cr₂O₇
•  KMnO₄
•  CH₃COONa
•  CuCl₂

CuCl₂

Q2. Which of the following aqueous solutions remains neutral after electrolysis?

•  CUSO₄
•  AgNO₃
•  K₂SO₄
•  NaCl

K₂SO₄

Q3. When electric current is passed through a cell having an electrolyte, the positive ions move towards the cathode and the negative ions towards the anode. If the cathode is pulled out of the solution

•  The positive and negative ions will move towards the anode
•  The positive ions will start moving towards the anode, the negative ions will stop moving
•  The negative ions will continue to move towards the anode and the positive ions will stop moving
•  The positive and negative ions will start moving randomly

The positive and negative ions will start moving randomly

Q4. The density of copper is 8.94 g mL^–1. Find the charge needed to plate an area of 10×10 cm² to thickness of 10^–2 cm using a CuSO₄ solution as electrolyte (atomic weight of Cu = 63.6)

•  2.7x10⁴C
•  8.8x10⁴C
•  18.3x10⁴C
•  1.7x10⁴C

2.7x10⁴C

Q5. During the purification of copper by electrolysis

•  The anode used are made of copper ore
•  Pure copper is deposited on the cathode, with the evolution of hydrogen at the cathode
•  The impurities such as Ag, Au, Zn and Fe go into solution
•  The voltage is carefully controlled to prevent the deposition of Zn and Fe at the cathode

The voltage is carefully controlled to prevent the deposition of Zn and Fe at the cathode

Q6. The platinum electrodes were immersed in a solution of cupric sulphate and electric current passed through the solution. After some time it was found that colour of copper sulphate disappeared with evolution of gas at the electrode. The colourless solution contains

•  Platinum sulphate
•  Copper hydroxide
•  Copper sulphate
•  Sulphuric acid

Sulphuric acid

Q7. Assertion (A): Sodium ions are discharged in preference to hydrogen ions at a mercury cathode
Reason (R): The nature of the cathode can affect the order of discharge of ions

•  Both A and R are true and R is a correct explanation of A
•  Both A and R are true but R is not a correct explanation of A
•  A is true but R is false
•  Both A and R are false

Both A and R are true and R is a correct explanation of A

Q8. Oxygen and hydrogen gas are produced at the anode and cathode during the electrolysis of dilute aqueous solutions of
I) Na₂SO₄
II) AgNO₃
III) H₂SO₄
IV) NaOH

•  Only I,II,IV are correct
•  Only I,II,III are correct
•  Only I,III,IV are correct
•  All of them are correct

Only I,III,IV are correct

Q9. Which of the following statements are correct?
I) The electrolysis of concentrated at H₂SO₄ at 0–5°C using a Pt electrode produces H₂S₂O₈
II) The electrolysis of a brine solution produces NaClO₃ and NaClO
III) The electrolysis of CuSO₄ solution using Pt electrodes causes the liberation of O₂ at the anode and the deposition of copper at the cathode
IV) All electrolytic reactions are redox reactions

•   Only I, II, IV are correct
•  Only I, II, III are correct
•  Only I, III, IV are correct
•  All of them are correct

All of them are correct

Q10. For electrosynthesis of a substance

•  △ G =+ve and Ecell =–ve
•  △ G =-ve and Ecell =+ve
•  △ G =-ve and Ecell =-ve
•  △ G =+ve and Ecell =+ve

△ G =+ve and Ecell =-ve