Q.1
A current of 2.0 A passed for 5 hours through a molten metal salt deposits 22.2 g of metal ( At Wt.=177]. The oxidation state of the metal in the metal salt is [ haryana CEET 1996]
  • a) +1
  • b) +2
  • c)+3
  • d)+4
Q.2
When a rod of metal A is dipped in an aqueous solution of metal B ( concentration of B2+=1M) at 25°C, the electrode potentials are A2+/A=-0.76 volts, B2+/B=+0.34 volts. [ KCET 1992]
  • a)A will gradually dissolve
  • b)B will deposit on A
  • c)No reaction will occur
  • d)Water will decompose into Hydrogen and Oxygen
Q.3
An unknown metal M displaces nickel from nickel(II) sulphate solution but does not displace manganese from manganese sulphate solution. Which order represents the correct order of reducing power
  • a) Mn > Ni > M
  • b) Ni > Mn > M
  • c) Mn > M > Ni
  • d) M > Ni > Mn
Q.4
The correct order of chemical reactivity with water according to electrochemical series is ..[MP PMT 1991]
  • a)K > Mg > Zn > Cu
  • b) Mg > Zn > Cu > K
  • c)K > Zn > Mg > Cu
  • d)Cu > Zn > Mg > K
Q.5
The standard EMF got the cell reactionZn + Cu2+ → Cu + Zn2+ is 1.1 Volt at 25°C The EMF for the cell reaction, when 0.1 M Cu2+ and 0.1M Zn2+ solution are used, at 25°C is [ Manipal PMT 2001]
  • a) 1.10 V
  • b) 0.10 V
  • c)-1.10V
  • d)-0.110 V
Q.6
The cell reaction in Daniel cell is [ KCET 1992]
  • a) Zn + Cu → Zn2+ + Cu2+
  • b) Zn2+ + Cu → Zn + Cu2+
  • c)Zn + Cu2+ → Zn2+ + Cu
  • d)Zn2+ + Cu2+ → Zn + Cu
Q.7
The voltage of a cell whose half cells are given below is Mg2+ + 2e- → Mg(s), -2.37 V Cu2+ + 2e- → Cu(s) , 0.34 V [EAMCET 1987]
  • a) -2.03 V
  • b) 1.36 V
  • c) 2.71 V
  • d) 2.03 V
Q.8
What is the amount of Chlorine evolved when 2 amp of current is passed for 30 minutes in an aqueous solution of NaCl? [ AIIMS 1999]
  • a)66 g
  • b) 1.32 g
  • c)33 g
  • d)99 g
Q.9
The standard reduction potential for Fe2+/Fe and S2+ Sn electrodes are -0.44 and -0.14 volt respectively. For the cell reaction:Fe2+ + Sn → Fe + Sn2+, the standard emf is [ IIT 1990] < img id="hidden8" width="67px" height="15px"class="hidden8"alt="" src="images/c.png"/>
  • a) +0.30 V
  • b) -0.58 V
  • c)+0.58 V
  • d)-0.30 V
Q.10
In a galvanic ell [ Pb CET 1994]
  • a) Chemical energy is converted into electricity
  • b) Chemical energy is converted into heat
  • c)Electrical energy is converted into heat
  • d)Electrical energy converted into chemical energy
Q.11
If half cell reaction A +e- → A- has a large negative reduction potential, it follows that ..[ MLNR 1992]
  • a) A is readily reduced
  • b) A is readily oxidized
  • c) A- is readily reduced
  • d) A- is readily oxidized
Q.12
Which of the following can be considered as a weal electrolyte [ harayana CEET 1991]
  • a)NaCl
  • b) HCl
  • c)CH3COOH
  • d)K2SO2
Q.13
The Nernst equation, Indicates that the equilibrium constant Kc will be equal to Q when
ch-7_que_no-289_img_no1.png
  • a)E=Eo
  • b) E=zero
  • c)Eo=1
  • d)RT/nF=1
Q.14
Four moles of electrons were transferred from anode to cathode in an experiment on electrolysis of water. the total volume of the two gases ( dry and at STP) produced will be approximately ( in liters) [ AIIMS 1993]
  • a) 22.4
  • b) 44.8
  • c)67.2
  • d)89.4
Q.15
Electrochemical equivalent of an element is [ CPMT 1991]
  • a)
    ch-7_qn-259choice_img_no1.png
  • b)
    ch-7_qn-259choice_img_no2.png
  • c)
    ch-7_qn-259choice_img_no3.png
  • d)
    ch-7_qn-259choice_img_no4.png
Q.16
if the number of moles of electrons involved in a reaction is doubled by multiplying all of the species appearing in the overall reaction by 2 then the [ Bihar MDAT 1994]
  • a) potential is halved
  • b) potential is doubled
  • c) potential is unchanged
  • d) potential is squared
Q.17
When current is passed through an electrolyte containing ions .. [ AFMC 1991]
  • a)all ions move to oppositely charged plates
  • b) ions do not move
  • c)all ions moves to respective charged plates
  • d)all the above facts are false
Q.18
Which of the following reaction occurs at the cathode during the charging of lead storage battery? [ BHU 1993]
  • a) Pb2+ + 2e- → Pb
  • b) Pb2+ + SO42- → PbSO4
  • c)Pb → Pb2+ +2e-
  • d)PbSO4 + 2H2O → 2PbO2 +4H+ + SO2- +2e-
Q.19
The conductivity of electricity required to liberate one gram equivalent of an element is called [ KCET 1992]
  • a) increases on dilution slightly
  • b) does not change on dilution
  • c)decreases on dilution
  • d)depends on density of electrolyte itself
Q.20
The hydrogen electrode is dipped in a solution of pH=3 at 25°C. The potential of the cell would be ( the value of 2.303RT/F is 0.059 V) [ KCET 1993]
  • a) 0.177 V
  • b) 0.087 V
  • c) -0.177 V
  • d) 0.059 V
Q.21
Which is not correct? the degree of dissociation of an electrolyte depends on [ MP PMT 1991]
  • a)Nature of the electrolytes
  • b) Catalytic action
  • c)Dilution
  • d)Temperature
Q.22
Standard reduction potentials for Li+/Li; Zn2+/Zn; H+/H2 and Ag+/Ag are -3.05, -0.762, 0.00 and +0.80V respectively. Which of the following has highest reduction capacity? [ MP PMT 1992]
  • a) Ag
  • b) H2
  • c)Zn
  • d)Li
Q.23
The electroplating with chromium is undertaken because [ MP PMT 1996]
  • a) Electrolysis of chromium is easer
  • b) Chromium can form alloy with other metals
  • c)Chromium gives protective and decorative coating to the base metal
  • d)Of the high reactivity of metallic chromium
Q.24
A cell constructed by coupling a standard magnesium electrode has emf of 2.7 volts. if the standard reduction potential of copper electrode is +0.34 volts, that of magnesium electrode is [ KCET 1989]
  • a) +3.04 volts
  • b) -3.04 volts
  • c) +2.36 volts
  • d) -2.36 volts
Q.25
When CuSO4 is electrolyzed by platinum electrodes [ CBSE PMT 1993]
  • a) Copper is liberated at cathode, sulphur at anode
  • b) Copper is liberated at cathode, oxygen at anode
  • c)Sulphur is liberated at cathode, oxygen at anode
  • d)Oxygen is liberated at cathode, copper at anode
Q.26
Given electrode potentials Fe3+ + e → Fe2+ , E=0.771 voltsI2 + 2e → 2I- , E=-0.536 voltsEcell for reaction 2Fe3+ + 2I- → 2Fe2+ + I2 is [ AIIMS 1994]
  • a) (2 × 0.0771) - 0.536)=1.006 volts
  • b) (0.771 - 0.5×0.536)=0.503 volt
  • c)0.771 - 0.536=0.235 volt
  • d)0.536 - 0.771=-0.235 volt
Q.27
The most durable metal plating on iron to protect against corrosion is [ CBSE PMT 1994]
  • a) Nickel plating
  • b) Copper plating
  • c)Tin plating
  • d)Zinc plating
Q.28
How many coulombs of electricity are required for reduction of 1 mole of MnO4- to Mn2+ ?
  • a) 96500 C
  • b) 1.93 × 105 C
  • c) 4.83 × 104
  • d) 1.93 × 102
Q.29
A Cell constant is generally found by measuring the conductivity of aqueous solution of ..[ MP PET 1991]
  • a)BaCl2
  • b) KCl
  • c)NaCl
  • d)MgCl2
Q.30
Reaction occurring at cathode is [ CPMT 1991]
  • a) Hydrolysis
  • b) Neutralisation
  • c)Oxidation
  • d)Reduction
0 h : 0 m : 1 s