121.

One percent composition of an organic compound A is, carbon : 85.71% and hydrogen 14.29%. Its vapour density is 14. Consider the following reaction sequence-

$\underline{\mathrm{A}} \stackrel{{\mathrm{Cl}}_2/ {\mathrm{H}}_2\mathrm{O}}{\to } \underline{\mathrm{B}} \underset{\left(\mathrm{ii}\right) {\mathrm{H}}_3{\mathrm{O}}^{+}}{\overset{\left(\mathrm{i}\right) \mathrm{KCN}/ \mathrm{EtOH}}{\to }} \underline{C}$

Identify $\underline{\mathrm{C}}$.

• CH₃CH(OH)-CO₂H

• HO-CH₂-CH₂-CO₂H

• HO-CH₂-CO₂H

• CH₃-CH₂-CO₂H

At 25°C, the molar conductances at infinite dilution for the strong electrolytes NaOH, NaCl and BaCl₂ are 248 × 10^-4, 126 × 10^-4 and 280 × 10^-4 Sm² mol^-1 respectively, ${\mathrm{\lambda }}_{\mathrm{m}}^{°}$ (BaOH)₂ in Sm² mol^-1 is

• 52.4 × 10^-4

• 524 × 10^-4

• 402 × 10^-4

• 262 × 10^-4

The number of molecules of CO₂ liberated by the complete combustion of 0.1 g atom of graphite in air is

• 3.01 × 10²²

• 6.02 × 10²³

• 6.02 × 10²²

• 3.01 × 10²³

19 g of a mixture containing NaHCO₃ and Na₂CO₃ on complete heating liberated 1.12 L of CO₂ at STP. The weight of the remaining solid was 15.9 g. What is the weight (in g) of Na₂CO₃ in the mixture before heating?

• 8.4

• 15.9

• 4.0

• 10.6

Solution 'X' contains Na₂CO₃ and NaHCO₃, 20 mL of X when titrated using methyl orange indicator consumed 60 mL of 0.1 M HCl solution. In another experiment, 20 mL of X solution when titrated using phenolphthalein, consumed 20 mL of 0.1 M HCl solution. The concentrations (in mol L^-1) of Na₂CO₃ and NaHCO₃ in X are respectively

• 0.01, 0.02

• 0.1, 0.1

• 0.01, 0.01

• 0.1, 0.01

The number of moles of electrons required to deposit 36 g of Al from an aqueous solution of Al(NO₃)₃ is (At. wt. of Al = 27)

• 4

• 3

• 2

• 1

A carbon compound contains 12.8% of carbon, 21.% of hydrogen and 85.1% of bromine. The molecular weight of the compound is 187.9. Calculate the molecular formula of the compound.

(Atomic weight : H = 1.008; C = 12.0; Br = 79.9)

• CH₃Br

• CH₂Br₂I

• C₂H₄Br₂

• C₂H₃Br₃

3.011 × 10²² atoms of an element weight 1.15 gm. The atomic mass of the element is

• 23

• 10

• 16

• 35.5

A gas 'X' is dissolved in water at 2 bar pressure. Its mole fraction is 0.02 in solution. The mole fraction of water when the pressure of gas is doubled at the same temperature is

• 0.04

• 0.98

• 0.96

• 0.02

KMnO₄ reacts with KI in basic medium to form I₂ and MnO₂. When 250ml of 0.1M KI solution is mixed with 250ml of 0.02M KMnO₄ in basic medium, what is the number of moles of I₂ formed?

• 0.015

• 0.0075

• 0.005

• 0.01