Chemistry 13_Objective_Phase VI
- If E0 (Fe3+/Fe) = – 0.036 V & E0‑(Fe2+/Fe) = – 0.439 V, the value of E0 (Fe3+, Fe2+/Pt) is
(A) – 0.475 V (B) 0.403 V
(C) 0.77V (d) 0.986 V
- The standard reduction potential of 2H2O + 2e– ¾® H2 + 2OH– at 298 K is
(A) 0.828 V (B) – 0.828 V
(C) 0.414 V (D) – 0.414V
- If E0 (Fe2+/Fe) = – 0.44V & E0(Pb2+/Pb) = – 0.13V, then adding powdered Pb & Fe to a solution containing 1 M in each of Pb2+ & Fe2+ ions would result into the formation of
(A) more of Pb & Fe2+ ions (B) more of Fe & Pb2+ions
(C) more of Fe & Pb (D) more of Fe2+ & Pb2+ ions
- In acidic medium Cr2O72– is converted to Cr3+ when it acts as an oxidising agent. The quantity of electricity required to reduce 0.05 mole of Cr2O72– would be
(A) 0.05 F (B) 0.1 F
(C) 0.2 F (D) 0.3 F
- The edge length of unit cell of sodium chloride is 564 pm. If the size of Cl– ion is 181 pm, the size of Na+ ion would be
(A) 383 pm (B) 282 pm
(C) 101 pm (D) 202 pm
- The co-ordination number of metal crystallizing in hexagonal close-packed (hcp) structure is
(A) 12 (B) 10
(C) 8 (D) 6
- Which of the following statements is correct?
(A) The co-ordination number of each type of ion in CsCl crystal is 8
(B) A metal that crystallizes in bcc structure has a co-ordination number of 12
(C) The length of the unit cell in NaCl is 552 pm ( = 95 pm, = 181 pm)
(D) The packing fraction for bcc structure is 0.52
- Copper displaces which of the metal from the salt solutions?
(A) AgNO3 (B) ZnSO4
(C) FeSO4 (D) All of the above
- Of the following metals, which one cannot be obtained by electrolysis of the aqueous solution of its salt is
(A) Ag (B) Mg
(C) Cu (D) Al
- How many electrons are there in one coulomb?
(A) 6.023 ´ 1023 (B) 96500
(C) 1.6 ´ 10–19 (D) 6.24 ´ 1018
- How much current is necessary to produce hydrogen gas at a rate of 1200 cc per second at NTP conditions?
(A) 96500 ampere (B) 48250 ampere
(C) 8.616 ampere (D) 14800 ampere
- The e.m.f. of half cell PtH2 (2 atm) | HCl (a = 0.02) & E0OP= 0 V is
(A) + 0.19 volt (B) + 0.403 volt
(C) – 0.409 volt (D) – 0.109 volt
- Given & . Then
(A) Ag+ can be reduced by H2 (B) Ag can oxidise H2(g) to H+
(C) Zn2+ can be reduced by H2 (D) Ag can reduce Zn2+
- The crystalline compound AxBy is characterised by a body-centered cell. The compound has the formula.
(A) AB (B) A4B
(C) A8B (D) AB4
- A solution of CuSO4 is electrolysed using platinum inert electrodes. Due to electrolysis, the colour changes from blue to _________ and pH of the solution ________.
(A) red, unaltered (B) colourless, increases
(C) blue, decreases (D) colourless, decreases,
- A solution of sodium sulphate is electrolysed using inert electrodes and the gases evolved are stored in a container. What is the mole fraction of gas in container which have higher concentration.
(A) (B) 0.33
(C) 2/3 (D) 4/5
(E) None
- The reduction potential of hydrogen half cell will be negative if
(A) = 1 atm and [H+] = 1 M (B) = 1 atm and [H+] = 2 M
(C) = 1.5 atm and [H+] = 1 M (D) = 1.2 atm and [H+] = 1.2 M
- A current of 1 ampere is passed through CuSO4 solution for 965 second. What mass of Cu is deposited at cathode?
(A) 0.3175 gm (B) 0.635 gm
(C) 0.15875 gm (D) 0.238 gm
- 1 faraday of electricity will deposit 108 gm of silver. What is electro-chemical equivalent of the substance?
(A) 1.119 ´ 10–3 (B) 2.238 ´ 10–3
(C) 0.108 (D) 1.08
- The mass of unit cell of CsCl corresponds to
(A) 1Cs+ and 1Cl– (B) 1Cs+ and 6Cl–
(C) 4Cs+ and 4Cl– (D) 8Cs+ and 1Cl–
- Which of the following is a non-crystalline solid
(A) CsCl (B) NaCl
(C) CaF2 (D) Glass
- Crystals of covalent compounds always have
(A) Atoms as their structural unit
(B) Molecules as their structural units
(C) Ions held together by electrostatic force
(D) High Melting point
- Tetragonal crystal system has the following unit cell dimensions
(A) a = b = c and a = b = g = 90°
(B) a = b ¹ c and a = b = g = 90°
(C) a = b ¹ c and a = b = g ¹ 90°
(D) a = b ¹ c and a = b = 90°; g = 120°
- The 8:8 type of packing is present in
(A) NaCl (B) KCl
(C) CsCl (D) MgF2
- Given
C + 2S ¾® CS2 DHf0 = + 117.0 kJ mol–1
C + O2 ¾® CO2; DHf0 = –393 kJ mol–1
S + O2 ¾® SO2; DHf0 = – 297 kJ mol–1
The heat of combustion of
CS2 + 3O2 ¾® CO2 + 2SO2 is
(A) – 807 kJ mol–1 (B) – 1104 kJ mol–1
(C) + 1104 kJ mol–1 (D) + 807 kJ mol–1
- If C(s) + O2(g) ¾® CO2(g); DH = X
and
CO(g) + O2 (g) ¾® CO2(g) DH = Y
Then the heat of formation of CO is
(A) X + Y (B) X – Y
(C) Y – X (D) X . Y
- Heat of neutralization is highest in the reaction between
(A) HNO3 – NH4OH (B) HCl – NaOH
(C) NH4OH – CH3COOH (D) NaOH – CH3COOH
- The energy change of reaction
C2H6(g) ¾® 2C(g) + 6H(g) is X kJ
The bond energy of C – H bond is
(A) X/6 kJ (B) X/3 kJ
(C) X kJ (D) indeterminate
- Which of the following describes the criterion of spontaneity
(A) DHT, p > 0 (B) DSTotal > 0
(C) DGT, P>0 (D) All of these
- For an endothermic reaction where DH represents the enthalpy of the reaction in kJ/mole, the minimum value for the energy of activation will be
(A) less than DH (B) zero
(C) more than DH (D) equal to DH
Answers
- C 62. B
- A 64. D
- C 66. A
- A 68. A
- B 70. D
- A 72. A
- A 74. A
- D 76. C
- C 78. A
- A 80. A
- D 82. A
- B 84. C
- B 86. B
- B 88. A
- B 90. C