Equation of Boyle's law is :

• $\frac{\mathrm{dP}}{\mathrm{P}}$ = -$\frac{\mathrm{dV}}{\mathrm{V}}$

• $\frac{\mathrm{dP}}{\mathrm{P}}$ = +$\frac{\mathrm{dV}}{\mathrm{V}}$

• $\frac{{\mathrm{d}}^2\mathrm{P}}{\mathrm{P}}$ = -$\frac{\mathrm{dV}}{\mathrm{dT}}$

• $\frac{{\mathrm{d}}^2\mathrm{P}}{\mathrm{P}}$ = +$\frac{{\mathrm{d}}^2\mathrm{V}}{\mathrm{dT}}$

A radioactive sample is emitting 64 times radiations than non-hazardous limit .If its half-life is 2 hours , after what time it becomes non- hazardous ?

• 16 h

• 10 h

• 12 h

• 8 h

Inert gases are mixed in iodine vapours. Then there are _____ between them.

• H-bonding

• van der Waals forces

• electrostatic forces

• metallic bonds

Critical temperatures for A, B, C and D gases are 25°C, 10°C, -80°C and 15°C respectively. Which gas will be liquefied more easily?

• A

• B

• C

• D

Assertion : If H₂ and Cl₂ enclosed separately in the same vessel exert pressure of 100 and 200 mm respectively, their mixture in the same vessel at the same temperature will exert a pressure of 300 mm.

Reason : Dalton's law of partial pressures states that total pressure is the sum of partial pressures.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Which is the correct relation for diffusion of gases :

• r $\propto$ d

• r $\propto$ $\sqrt{\mathrm{d}}$

• r $\propto$ $\frac{1}{\sqrt{\mathrm{d}}}$

• none of these

If the r.m.s. speed of a gaseous molecule is x m/sec at a pressure P atm , then what will be the r.m.s. speed at a pressure 2P atm and constant temperature ?

• x

• 2x

• 4x

• x/4

The solution obtained by adding water to alcohol, shows :

• +ve deviation from Raoult's law

• ideal behaviour

• -ve deviation from Raoult's law

• application of Henry's law

If P is pressure and $\mathrm{\rho }$ is density of a gas, then P and $\mathrm{\rho }$ are related as :

• P $\propto$ $\mathrm{\rho }$

• P $\propto \left(\frac{1}{\mathrm{\rho }}\right)$

• P $\propto {\mathrm{\rho }}^2$

• P $\propto \left(\frac{1}{{\mathrm{\rho }}^2}\right)$

Intermolecular hydrogen bonding is strongest in

• methylamine

• phenol

• formaldehyde

• methanol