If two gases are present in a container, the total pressure in the container is equal to
a. the sum of the pressures that are exerted by each of the two gases.
b. twice the sum of the pressures that are exerted by the individual gases.
c. the sum of the pressures that each gas would exert if they occupied twice the volume.
d. the sum of the pressures that each gas would exert if they occupied half the volume.

The correct option is (a).

Explanation:

If two gases are present in a container, the total pressure in the container is equal to the sum of the all the individual pressures exerted by the individual gases in a container.

Individual pressure exerted by the individual gas in a container is called partial pressure of that individual gas.

So, total pressure of gas in container is:

Where = Total pressure exerted by the gases in the container.

= Partial pressure of gas 'a'

= partial pressure of gas 'b'

The answer is a, because the question is referring to partial pressures. Partial pressures are a mere sum, no halving or doubling of anything is necessary.

So, A

Hope this helped :)

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.