Methane contributes towards global warming so it is called a _________________ gas.

 

Strength of concrete increases with increase in water cement ratio as the strength of the cement is directly proportional to water cement ratio.

Coagulation :: The action or process of a liquid, especially blood, changing to a solid or semi-solid state.

An acid can be defined as a molecule or other species which can donate a proton or accept an electron pair in reactions.

(OR)

A substance with particular chemical properties including turning litmus red, neutralizing alkalis, and dissolving some metals; typically, a corrosive or sour-tasting liquid of this kind.

The boiling point of the compounds depend on the number of carbons in them. Hexane has 6, Pentane has 5 and Propane has 3 carbons. As Hexane is with 6 carbons it has highest boiling point and next Pentane with 5 and lowest Propane with 3.