An irregularly shaped stone was lowered into a graduated cylinder holding a volume of water equal to 2 ml. the height of the water rose to 7 ml. if the mass of the stone was 25 g, what was its density

The density of the stone whose mass is 25 g and its volume is 5 mL is 5 g/mL.

We have a graduated cylinder holding a volume of water equal to 2 mL. After a stone is added, the height of the water rose to 7 mL. The volume of the stone is equal to the difference in the levels of water.

The stone has a volume of 5 mL and a mass of 25 g. Its density, that is the ratio of the mass to the volume, is:

The density of the stone whose mass is 25 g and its volume is 5 mL is 5 g/mL.

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The density of the stone is 5 g/cm³.

Mass = 25 g

Volume = 7 mL – 2 mL = 5 mL = 5 cm³

Density = mass/volume = 25 g/5 cm³ = 5 g/cm³

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.