1.

The number of lone pair(s) of electrons on the central atom is [BrF₄]^-, XeF₆ and [SbCl₆]^3- are, respectively

• 2, 1 and 1

• 2, 1 and 0

• 2, 0 and 1

• 1, 0 and 0

The lewis acidity of BF₃ is less than BCl₃ even though fluorine is more electrongative than chlorine. It is due to

• stronger 1p (B)-3p(Cl) σ- bonding

• stronger 2p(B) - 3p(Cl) π-bonding

• stonger 2p(B) - 2p(F)  σ- bonding

• stronger 2p(B)- 2p(F) π-bonding

If enthaplies of formation for C₂H₂(g), CO₂(g) and H₂O(l) at 25°C and 1atm pressure be 52, -394 and -286kJ mol^-1 respectively, then the enthaply of combustion of C₂H₄(g) will be

• -141.2 kJ mol^-1

• -1412 kJ mol^-1

• + 141.2 kJ mol^-1

• + 1412 kJ mol^-1

8.50g of NH₃ is present in 250ml volume. Its active mass is

• 1.5 ML^-1

• 2.0 ML^-1

• 1.0 ML^-1

• 0.5 ML^-1

The equilibrium constants of the reactions

${\mathrm{SO}}_2\left(\mathrm{g}\right) + \frac{1}{2}{\mathrm{O}}_2\left(\mathrm{g}\right) \rightleftharpoons {\mathrm{SO}}_3\left(\mathrm{g}\right)$ and $2{\mathrm{SO}}_2\left(\mathrm{g}\right) + {\mathrm{O}}_2\left(\mathrm{g}\right) \rightleftharpoons 2{\mathrm{SO}}_3\left(\mathrm{g}\right)$ are K₁ respectively. The relationship between K₁ and K₂ will be

• ${\mathrm{K}}_1^2=$K₂

• K₂ = √K₁

• K₁= K₂

• ${\mathrm{K}}_2^3 = {\mathrm{K}}_1$

The geometry around the central atom in ClF${}_4^{+} \mathrm{is}$

• octahedral

• trigonal bipyramidal

• square planar

• square pyramidal

Among the following, the equilibrium which is not affected by an increase in pressure is

• C(s) + H₂O (g) $\rightleftharpoons$ CO(g) + H₂(g)

• 3Fe(s) + 4H₂O (g) $\rightleftharpoons$Fe₃O₄ (s) + 4H₂(g)

• 2SO₃(g) $\rightleftharpoons$2SO₂(g) + O₂ (g)

• H₂ (g) + I₂(s) $\rightleftharpoons$2Hi(g) 

Which one of the following is not a unit of energy?

• lit-atm

• Kg m²s^-2

• Nm

• kg ms^-2

When a liquid that is immiscible with water was steam distilled at 95.2°C at a total pressure of 99.652 kPa. The distillate contained 1.27 g of the liquid per gram of water. What will be the molar mass of the liquid if the vapour pressure of water is 85.140 kPa at 95.2°C?

• 99.65 g mol^-1

• 18 g mol^-1

• 134.1 g mol^-1

• 105.74 g mol^-1

What is pH of 2 x 10^-8 molar HCl solution? Here, log 2 = 0.301 and log 3 = 0.477.

• 6.92

• 9.5

• 5.4

• 7.7