The inert gas found most abundant in the atmosphere is

• He

• Ne

• Ar

• Kr

Water gas is produced by

• Passing steam over red hot coke

• Passing steam and air over red hot.

• Burning coke is excess air.

• Burning coke is limited supply of air.

The strongest base among the following is

• Amide ion

• Hydroxide ion

• Trimethylamine

• Ammonia

The correct descending order of the heat liberated (in kJ) during the neutralisation of the, acids CH₃COOH (W), HF (X), HCOOH (Y) and HCN (Z) under identical conditions (K_a of CH₃COOH = 1.8 × 10^-5, HCOOH =1.8 × 10^-10 HCN = 4.9 × 10^-10 and HF = 3.2 × 10^-4)

• Y > X > Z > W

• X > Y > W > Z

• W > X > Y > Z

• Z > W > Y > X

How many times a 0.1 M strong monobasic acid solution should be diluted so that pH of the resulting solution is tripled?

• 50

• 10

• 25

• 100

The equilibrium pressure for the given reaction, is  $\mathrm{\pi }$/4 atm at 400 K. The K_p for the given reaction (in atm²) is

MSO₄.2H₂O (s) $\rightleftharpoons$ MSO₄ (s) + 2H₂O (g)

• ${\mathrm{\pi }}^2 / 4$

• $\mathrm{\pi } / 6$

• ${\mathrm{\pi }}^2 / 16$

• $\mathrm{\pi } / 16$

467.

The low solubility of LiF and that of CsI in water are respectively due to which of the following properties of the alkali metal ions?

• Higher hydration enthalpy of Li, higher lattice enthalpy of Cs⁺

• Smaller hydration enthalpy of Li, higher lattice enthalpy of Cs⁺

• Smaller lattice enthalpy of Li, higher hydration enthalpy of Cs⁺

• Higher lattice enthalpy of Li, smaller hydration enthalpy of Cs⁺

The relative strength of trichlorides of boron group to accept a pair of electron is given by

• GaCl₃ > AlCl₃ > BCl₃

• AlCl₃ > BCl₃ > GaCl₃

• AlCl₃ > GaCl₃ > BCl₃

• BCl₃ > AlCl₃ > GaCl₃

If the ionic product of M (OH)₂ is 5 × 10^-10, then the molar solubility of M(OH)₂ in 0.1 M NaOH is

• 5 × 10^-12 M

• 5 × 10^-8 M

• 5 × 10^-10 M

• 5 × 10^-9 M

Equilibrium constants are given for the following two equilibria.

(i) A₂ (g) + B₂ (g) $\rightleftharpoons$ 2AB (g); K = 2 × 10^-4 L mol^-1

(ii) 2AB (g) + C₂ (g) $\rightleftharpoons$ 2ABC (g); K = 2 × 10^-2 L mol^-1

Calculate the equilibrium constant for the following equilibrium.

ABC (g) $\rightleftharpoons$ $\frac{1}{2}$A₂ (g) + $\frac{1}{2}$B₂ (g) + $\frac{1}{2}$C₂ (g)

• 500 mol^1/2 L^-1/2

• 500 mol^1/2 L^1/2

• 4 × 10^-6 mol^1/2 L^1/2

• 200 mol^1/2 L^-1/2