Science (English Medium) कक्षा १२ - CBSE Question Bank Solutions

The quantity of charge required to obtain one mole of aluminium from Al₂O₃ is ______.

`E_(cell)^Θ` for some half cell reactions are given below. On the basis of these mark the correct answer.

(a) \[\ce{H^{+} (aq) + e^{-} -> 1/2 H_2 (g); E^Θ_{cell} = 0.00V}\]

(b) \[\ce{2H2O (1) -> O2 (g) + 4H^{+} (aq) + 4e^{-}; E^Θ_{cell} = 1.23V}\]

(c) \[\ce{2SO^{2-}_{4} (aq) -> S2O^{2-}_{8} (aq) + 2e^{-}; E^Θ_{cell} = 1.96V}\]

(i) In dilute sulphuric acid solution, hydrogen will be reduced at cathode.

(ii) In concentrated sulphuric acid solution, water will be oxidised at anode.

(iii) In dilute sulphuric acid solution, water will be oxidised at anode.

(iv) In dilute sulphuric acid solution, \[\ce{SO4^{2-}}\] ion will be oxidised to tetrathionate ion at anode.

`E_(cell)^Θ` = 1.1V for Daniel cell. Which of the following expressions are correct description of state of equilibrium in this cell?

(i) 1.1 = `K_c`

(ii) `(2.303RT)/(2F) logK_c` = 1.1

(iii) `log K_c = 2.2/0.059`

(iv) `log K_c` = 1.1

For the given cell, \[\ce{Mg | Mg^{2+} || Cu^{2+} | Cu}\]

(i) \[\ce{Mg}\] is cathode

(ii) \[\ce{Cu}\] is cathode

(iii) The cell reaction is \[\ce{Mg^+ Cu^{2+} -> Mg^{2+} + Cu}\]

(iv) \[\ce{Cu}\] is the oxidising agent

Can absolute electrode potential of an electrode be measured?

Depict the galvanic cell in which the cell reaction is \[\ce{Cu + 2Ag^+ -> 2Ag + Cu^{2+}}\]

What is electrode potential?

Consider the following diagram in which an electrochemical cell is coupled to an electrolytic cell. What will be the polarity of electrodes ‘A’ and ‘B’ in the electrolytic cell?

A galvanic cell has electrical potential of 1.1V. If an opposing potential of 1.1V is applied to this cell, what will happen to the cell reaction and current flowing through the cell?

How will the pH of brine (aq. \[\ce{NaCl}\] solution) be affected when it is electrolysed?

Consider a cell given below:
\[\ce{Cu | Cu^{2+} || Cl^{-} | Cl_{2},Pt}\]
Write the reactions that occur at anode and cathode

Match the terms given in Column I with the units given in Column II.

Match the terms given in Column I with the items given in Column II.

Match the items of Column I and Column II.

Assertion: E_Cell should have a positive value for the cell to function.

Reason: `"E"_("cathode") < "E"_("anode")`

Assertion: Mercury cell does not give steady potential.

Reason: In the cell reaction, ions are not involved in solution.

The term ‘sorption’ stands for ______.

Which one of the following is not applicable to the phenomenon of adsorption?

Which of the following is an example of absorption?

On the basis of data given below predict which of the following gases shows least adsorption on a definite amount of charcoal?