Why do gases always tend to be less soluble in liquids as the temperature is raised?

Why is the reduction of a metal oxide easier if the metal formed is in liquid state at the temperature of reduction?

Which law states the relation between solubility of gas in liquid at constant temperature and external pressure ?

Why do high altitude areas have brighter sunlight and lower temperatures as compared to the plains.

H_2S is a gas while H_2O is liquid at room temperature·? Why ?

Name one metal and non-metal that exist in liquid state at room temperature. Also name two metals having melting point less than 310K (37^@C) .