# States of Matter Important Questions

Question 1
What is the difference between Diffusion and Effusion

Question 2
Why it is not possible to cool a gas at 0 K?

Question 3
Why it is difficult to cook at hills?

Question 4
What is Surface Tension? and what is the effect of temperature on the surface tension of the liquid

Question 5
Distiguish between Boiling point, Normal boiling point and Standard boiling point

Question 6
Both $N_2O$ and $CO_2$ have similar rate of diffusion under the same P & T why?

Question 7
Write difference between Real and Ideal gas?

Question 8
Define compressibility factor of the gas ? What is the value for Ideal Gas?

Question 9
What is Gay Lussac's law?

Question 10
State the relationship between the rate of the diffusion of gas and its molecular mass?

Question 11
Why are aerated water bottles kept under water during summer?

Question 12
What is the unit of Van der Waals constant 'a' ?

## Numericals

Question 1
Calculate the volume occupied by 8.8 g of $CO_2$ at 31.1 ° C and 1 Bar pressure

Question 2
At room temperature ammonia gas at one atmosphere pressure and hydrogen chloride has at P atm pressure are allowed to effuse through identical pin holes from opposite ends of a glass tube of 1 meter length and of uniform cross-section. Ammonia chloride($NH_4CL$) is first formed at a distance of 60 cm from the end through whihc HCL has is sent in. What is the value of P? ( Ans 4.8 atm)

Question 3
Certain application require to increse the volume of 100 cm3 of a gas by 30% without changing the pressure. To what temperature the gas be heated if its intial temperature is 25° C

Question 4
The ratio between the rate of diffusion of an unknown gas (x) and $CO_2$ Is 40:45 Find out the molecular mass of unknown gas (x) (Ans 55.68)

Question 5
What is the pressure exerted by a mixture of 3.5 g of Nitrogen and 2 g of helium gas when confined in a volume of 50 litre and 0 ° C? ( Ans .28 atm)

Question 6
A sealed iron container 4 m3 of nitrogen gas at .99 atm and 25° C is thrown into fire where the tempertaure is 1100° . What is the new pressure of the gas in the container assuming constant volume and ideal behaviour? (Ans 4.56 atm)

Question 7
The compressiibility factor for nitrogen at 223 K and 800 atm i 1.95 and at 373 K and 200 atm is 1.1. A certain mass of nitrogen occupies a volumne of 1 dm3 at 223 K and 800 atm. Calculate the volume occupied by the same quantity of nitrogen at 373 K and 200 atm (Ans 3.77 Litre)

Question 8
A open vessel at 300 K is heated until 3/5 of the air in it has been expelled. Assuming that volume of the vessel remain constant, find the temperature to which the vessel has been heated? ( Ans 750 K)

Question 9
A gas occupies 600 mL volume at 25° C and 760 mm pressure.What will be pressure at height where temperature is 10° C and volume of gas us 640 mL?

Question 10
The composition of the air inhaled bya human is 21% by volume $O_2$ and .03% $CO_2$ and that of exhaled air is 16% $O_2$ and 4.4 $CO_2$. Assuming a typical volume of 7200 L/day.what mass of $O_2$ is used by the body and what mass of $CO_2$ is generated by the body each day.We can Assume ideal gas behaviour for the air at 37° C and 1 atm ( 452.8g, 544.06 g)