How many joules are absorbed when 64.3 grams of water is heated from 40.0 °c to 74.0 °c?
a. 7,330 joules
b. 9,150 joules
c. 10,100 joules
d. 12,800 joules

Answer : The correct option is, (B) 9150 joules

Explanation : Given,

Initial temperature =

Final temperature =

Mass of water = 64.3 g

Specific heat of water =

Formula used :

or,

where,

Q = heat absorbed = ?

m = mass of water

= specific heat of water

= initial temperature

= final temperature

Now put all the given value in the above formula, we get:

Therefore, the heat absorbed will be, 9150 J

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.