Which among the following gases can be liquified easily?

• Chlorine

• Nitrogen

• Oxygen

• Hydrogen

The plot of square root of frequency of X-ray emitted against atomic number led to suggestion of which law/rule?

• Periodic law

• Modern periodic law

• Hund's rule

• Newland's law

If average velocity of a sample of gas molecules at 300 K is 5 cm s^-1, what is RMS velocity of same sample of gas molecules at the same temperature? (Given, α: u: v = 1:1.224: 1.127)

• 6.112 cm/s

• 4.605 cm/s

• 4.085 cm/s

• 5.430 cm/s

20 mL solution of 0.1 M ferrous sulphate was completely oxidised using a suitable oxidising agent. What is the number of electrons exchanged?

• 1.204 x 10²²

• 193

• 1930

• 1.204 x 10²¹

The volume of oxygen evolved at STP by decomposition of 0.68 g '20 volume' hydrogen peroxide solution is

• 2.24mL

• 22.4mL

• 224mL

• 2240mL

What is the molality of a solution containing 200 mg of urea (molar mass 60 g mol^-1) dissolved in 40 g of water?

• 0.0825

• 0.825

• 0.498

• 0.0013

The work done when two mole of an ideal gas is compressed form a volume of 5 m³ to 1 dm³ at 300 K, under a pressure of 100 kPa is

• 499.9kJ

• -499.9 kJ

• -99.5 kJ

• 42495 kJ

Assuming enthalpy of combustion of hydrogen at 273 K is -286 kJ and enthalpy of fusion of ice at the same temperature to be +6.0 kJ, calculate enthalpy change during formation of 100 g of ice.

• +1622 kJ

• - 1622 kJ

• +292 kJ

• - 292 kJ

What is the orbital angular momentum of an electron in 'f'  orbital?

• $\frac{1.5\mathrm{h}}{\mathrm{\pi }}$

• $\frac{\sqrt{6}\mathrm{h}}{\mathrm{\pi }}$

• $\frac{\sqrt{3}\mathrm{h}}{\mathrm{\pi }}$

• $\frac{\sqrt{3}\mathrm{h}}{2\mathrm{\pi }}$

The product of molar concentrations of hydrogen ions and hydroxide ions in a 0.01 M aqueous solution of sodium chloride is known as

• hydrolysis constant of salt

• dissociation constant of acid

• dissociation constant of base

• ionic product of water