Multiple Choice Questions on Electrochemistry
1- The salt bridge in the electro-chemical cell is used to
(A) Increase the voltage of the cell
(B) Increase the oxidation / reduction rate
(C) Maintain electrical neutrality
(D) Increase the rate at which equilibrium is attained
2- Select the correct statement regarding glass electrode
(A) Easily influenced by oxidizing and reducing agents
(B) Suitable for analytes with high alkali metal content
(C) It is not poisoned by heavy metals
(D) It can work at temperature down 0°C
3- Which one of the following can be used to measure pH?
(A) A glass electrode
(B) A concentration cell
(C) A hydrogen electrode
(D) All of the above
4- Which one of the following statements associated with batteries is incorrect?
(A) Secondary batteries are rechargeable
(B) Electrodes with greater surface area give a greater potential
(C) The cell reaction in a primary battery is not reversible
(D) In a dry cell, the reaction Zn ® 2n2+ continues to occur even when the battery is not being used
5- Cans made from iron deteriorate rapidly in the environment, whereas aluminium cans have much longer lifetime. This is due to:
(A) Low density of aluminium.
(B) Higher reactivity of Iron.
(C) Corrosion products of aluminium formed initially adhere more tightly to the underlying metal and protect further corrosion.
(D) Corrosion products of iron are soluble in water unlike those of aluminium.
6- The salt bridge in the electrochemical cell serves to
(A) increase the rate at which equilibrium is attained
(B) increase the voltage of the cell
(C) maintain electrical neutrality
(D) increase the oxidation/reduction rate
7- Which of these statements about a galvanic cell are not true ?
(i) The cathode carries a positive sign
(ii) The anions migrate towards cathode
(iii) The electrons are released through the anode
(iv) Reduction occurs at anode
(A) (ii) and (iv)
(B) (ii) and (iii)
(C) (i) and (ii)
(D) (i) and (iii)
8- The unit of specific conductance is …………
(A) Ohm cm-1
(B) Ohm-1 cm
(C) Ohm-1 cm-1
(D) Ohm cm
9- Among the following: Lead, iron, chromium and copper; the least easily oxidised metal is …..
(A) Lead
(B) Copper
(C) Chromium
(D) Iron
10- The distance between two electrodes of a cell is 3.0 cm and area at each electrode is 6.0 cm. The cell constant will be ……….
(A) 1.0
(B) 0.5
(C) 2.0
(D) 18
11- Which one of the following will decompose on passing electric current?
(A) Silver nitrate
(B) Ethyl alcohol
(C) Urea
(D) Glucose
12- Which one of the following pairs of electrolytes will not show common ion effect
(A) HCl + H2S
(B) NaCl + NH4Cl
(C) HCl + CH3COOH
(D) NH4Cl + NH4OH
13- Zeta potential is also called ……….
(A) Electrophoretic potential
(B) Electrokinetic potential
(C) Electro osmosis potential
(D) Nernst potential
ANSWERS:
1-(C), 2-(A), 3-(D), 4-(C), 5-(C), 6-(C), 7-(D), 8-(B), 9-(B), 10-(B), 11-(A), 12-(B), 13-(B)