Important reasoning Questions of "the state of matter" !!

(1) Liquid ammonia bottle is cooled before opening the seal. Explain.

The molecular speeds of gaseous molecules are analogous to those of rifle bullets; why is then odour of the gaseous molecule not detected so fast?

(2) Carbon dioxide is heavier than oxygen and nitrogen but is does not form the lower layer of the atmosphere. Explain.

(3) Out of dry air and wet air, which is heavier?

(4) Can we apply Dalton’s law of partial pressure to a mixture of carbon monoxide and oxygen?

(5) Why a bottle of liquid ammonia is cooled before opening the seal?

(6) Explain , Aerated water bottles are kept under water during summer why?

(7) Arrange the following in the increasing order of melting point of different types of crystalline solid

 (i) Covalent solid 

(ii) Metallic solid 

(iii) Molecular 

(iv) Ionic

(8) Why falling liquid drops are spherical?

(9) Why diethyl ether has higher vapour pressure than ethyl alcohol at a particular temperature?

(10) Why liquid have a definite volume but no definite shape?

(11) What are the difference between Diffusion and Effusion ?

(12) What is payload of Balloon ?

(13) What is Aqueous tension ?

(14) What is Vander waals equation of state of a real gas ?

(15) What is Boyle's temperature ? and what is relation of Boyle's temperature with Vander waal's constant?

 

The pH of at which an acid indicator with Ka is 10^-15 changes colour when indicator concentration 1×10^-5 M is?

SOLUTION:

An indicator with Ka = 10^-5 is solution with pH = 6 Calculate % of indicator in ionised form?

SOLUTION:

For acidic indicator, pH range is 3 to 4.6 calculate the ratio of[ In- ] and H+ for the appearance of solution in a single colour.

SOLUTION:

Given pH range 3.0 to 4.6 so pK_In= (3.0+ 4.6)/2 =3.6

For an indicator pKa is 6 Calculate pH of Solution having this indicator such that 40% indicator molecules remain in ionised form.

SOLUTION:  We know that