The final temperature of the water mixture if no heat is lost?

The final temperature of the water mixture is 297 K.

Explanation:

It is said in the question that no heat is lost so we can conclude that heat lost is equal to heat absorbed by the sample.

The heat energy absorbed or lost can be calculated from the equation:

q=m.c. change in temperature

q= heat gain or loss

m = mass of the sample

c= specific heat of the substance

change in temperature

Heat loss will be equal to heat gain as the temperature difference is large between the samples.

-Δt Heat loss =Δ heat gain

So by comparing the heat absorbed or lost.

mhot. c.Δt hot= mcold.c.Δt cold

-0.526. 2.01.(ΔTf- 446) = 4.186. 4.18.(ΔTf-288)

-1.0572ΔTf+ 471.53= 17.49 ΔT- 5039.27

ΔTf= 297K

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.