The number of chlorine atoms in 20 mL of chlorine gas at STP is _________ 10²¹. (Round off to the Nearest Integer).

[Assume chlorine is an ideal gas at STP

R = 0.083 L bar mol^$$-$$1 K^$$-$$1, N_A = 6.023 $$\times$$ 10²³]

The pressure exerted by a non-reactive gaseous mixture of 6.4g of methane and 8.8 g of carbon dioxide in a 10L vessel at 27$$^\circ$$C is __________ kPa. (Round off to the Nearest Integer).

[Assume gases are ideal, R = 8.314 J mol^$$-$$1 K^$$-$$1

Atomic masses : C : 12.0 u, H : 1.0 u, O : 16.0 u]

3.12 g of oxygen is adsorbed on 1.2 g of platinum metal. The volume of oxygen adsorbed per gram of the adsorbent at 1 atm and 300 K in L is __________.

[R = 0.0821 L atm K^$$-$$1mol^$$-$$1]

A certain gas obeys P(V_m $$-$$ b) = RT. The value of $${\left( {{{\partial Z} \over {\partial P}}} \right)_T}$$ is $${{xb} \over {RT}}$$. The value of x is _________. (Integer answer) (Z : compressibility factor)