JEE Advance - Chemistry (1990)

• 1

  Calculate the molality of 1 litre solution of 93% H₂SO₄ (weight/volume). The density of the solution is 1.84 g/ml

  回答

  (C)

  10.42 m
• 2

  The oxidation number of phosphorus in Ba(H₂PO₂) is :

  回答

  (C)

  +1
• 3

  A mixture of H₂C₂O₄ (oxalic acid) and NaHC₂O₄ weighing 2.02 g was dissolved in water and solution made upto one litre. Ten millilitres of the solution required 3.0 ml. of 0.1 N sodium hydroxide solution for complete neutralization. In another experiment, 10.0 ml. of the same solution, in hot dilute sulphuric acid medium. require 4.0 ml. of 0.1 N potassium permanganate solution for complete reaction. Calculate the amount of H₂C₂O₄ and NaHC₂O₄ in the mixture.

  回答

  (C)

  H2C2O4 = 1.12 g, NaHC2O4 = 0.90 g
• 4

  A solid mixture (5.0 g) consisting of lead nitrate and sodium nitrate was headed below 600^oC until the weight of the residue was constant. If the loss in weight 28.0 percent, find the amount of lead nitrate and sodium nitrate in the mixture.

  回答

  (A)

  Pb(NO3)2 = 3.324 g, NaNO3 = 1.676 g
• 5

  According to Bohr's theory, the electronic energy of hydrogen atom in the n^th Bohr's orbit is given by $${E_n} = {{ - 21.6 \times {{10}^{ - 19}}} \over {{n^2}}}J$$. Calculate the longest wavelength of light (in Å) that will be needed to remove an electron from the third Bohr orbit of the He⁺ ion.

  回答

  (A)

  2055 Å
• 6

  Amongst the following elements (whose electronic configuration are given below), the one having the highest ionization energy is:

  回答

  (B)

  [Ne] 3s²3p³
• 7

  The shape of [CH₃]⁺ is _____.

  回答

  (D)

  planar
• 8

  The presence of polar bonds in a poly-atomic molecule suggests that the molecule has non-zero dipole moment.

  回答

  (B)

  FALSE
• 9

  When zeolite, which is hydrated sodium aluminium silicate is treated with hard water the sodium ions are exchanged with

  回答

  B

  D
• 10

  The freezing point of equimolal aqueous solutions will be highest for

  回答

  (D)

  C₆H₁₂O₆ (glucose)
• 11

  The vapour pressure of pure benzene at a certain temperature is 640 mm Hg. A non-volatile non-electrolyte solid weighing 2.175 g is added to 39.0 g of benzene. The vapour pressure of the solution is 600 mm Hg. What is the molecular weight of the solid substance?

  回答

  (B)

  65.25
• 12

  Give the IUPAC name of the following compound :

  

  回答

  (A)

  5,6-diethyl-3-methyldec-4-ene