JEE Advance - Chemistry (1983)

• 1

  Complete and balance the following equation:
  
  Ce³⁺ + $$S_2O_8^{-2} \to $$ $$SO_4^{-2}$$ + Ce⁴⁺

  Odpowiedź

  (C)

  2Ce³⁺ + $$S_2O_8^{-2} o $$ $$2SO_4^{-2}$$ + 2Ce⁴⁺
• 2

  Complete and balance the following equation:
  
  Zn + $$NO_3^- \to$$ Zn²⁺ + $$NH_4^+$$

  Odpowiedź

  (A)

  4Zn + $$NO_3^- + 10H^+ \to$$ 4Zn²⁺ + $$NH_4^+$$ + 3H₂O
• 3

  Complete and balance the following equation:
  
  $$Cr_2O_7^{2-}$$ + C₂H₄O $$\to$$ C₂H₄O₂ + Cr³⁺

  Odpowiedź

  (B)

  $$Cr_2O_7^{2-} + 14H^+ + 3C_2H_4O \to 3C_2H_4O_2 + 2Cr^{3+} + 7H_2O$$
• 4

  The density of a 3 M Sodium thiosulphate solution (Na₂S₂O₃) is 1.25 g per ml. Calculate
  
  (i) the percentage by weight of sodium thiosulphate,
  
  (ii) the mole fraction of sodium thiosulphate and
  
  (iii) the molalities of Na⁺ and $$S_2O_3^{-2}$$ ions

  Odpowiedź

  (A)

  (i) 37.92, (ii) 0.065, (iii) 7.732m, 3.865m
• 5

  3 g of a salt of molecular weight 30 is dissolved in 250 g of water. The molality if the solution is _____.

  Odpowiedź

  (D)

  0.4 m
• 6

  Complete and balance the following equation:
  
  Zn + $$NO_3^- \to$$ Zn²⁺ + $$NH_4^+$$

  Odpowiedź

  (A)

  4Zn + NO3- + 10H+ → 4Zn2+ + NH4+ + 3H2O
• 7

  Linear overlap of two atomic p-orbitals leads to a sigma bond.

  Odpowiedź

  (A)

  TRUE
• 8

  An organic compound C_xH_2yO_y was burnt with twice the amount of oxygen needed for complete combustion of CO₂ and H₂O. The hot gases when cooled to 0^oC and 1 atm pressure, measured 2.24 litres. The water collected during cooling weighed 0.9 g. The vapour pressure of pure water at 20^oC is 17.5 mm Hg and is lowered by 0.104 mm when 50 g of the organic compound are dissolved in 1000 g of water. Give the molecular formula of the organic compound.

  Odpowiedź

  (D)

  C5H10O5
• 9

  Heavy water is

  Odpowiedź

  (C)

  D₂O
• 10

  The absorption of hydrogen by palladium is commonly known as ______.

  Odpowiedź

  (C)

  Occlusion
• 11

  Which one among the following does not have the hydrogen bond?

  Odpowiedź

  (D)

  liquid HCl
• 12

  The types of bonds present in CuSO₄.5H₂O are only

  Odpowiedź

  (C)

  electrovalent, covalent and coordinate covalent
• 13

  Carbon tetrachloride has no net dipole moment because of

  Odpowiedź

  (B)

  its regular tetrahedral structure
• 14

  Rutherford's scattering experiment is related to the size of the

  Odpowiedź

  (A)

  nucleus
• 15

  Any p-orbital can accommodate upto

  Odpowiedź

  (D)

  two electrons with opposite spins
• 16

  The principal quantum number of an atom is related to the

  Odpowiedź

  (A)

  size of the orbital
• 17

  The energy of the electron in the 3d-orbital is less than that in the 4s-orbital in the hydrogen atom.

  Odpowiedź

  (B)

  FALSE
• 18

  Gamma rays are electromagnetic radiations of wavelengths of 10^-6 to 10^-5 cm

  Odpowiedź

  (B)

  FALSE
• 19

  Elements of the same mass number but of different atomic numbers are known as ____.

  Odpowiedź

  (D)

  isobars
• 20

  Complete and balance the following equations:
  
  Cl₂ + OH^- $$\to$$ Cl^- + ClO^-

  Odpowiedź

  (B)

  Cl2 + 2OH- $$ o$$ Cl- + ClO- + H2O
• 21

  Complete and balance the following equation:
  
  HNO₃ + HCl $$\to$$ NO + Cl₂

  Odpowiedź

  (A)

  3HNO₃ + 6HCl $$ o$$ NO + 3Cl₂ + 2H₂O