Explain how methane (ch4) and ethane (c2h6) demonstrate the law of definite composition and the law of multiple proportions

Law of definite composition: The elements which are present in the compound is combined in the same proportion by mass.

Law of multiple proportion: When two or more compounds are formed by the combination of two elements then the mass ratio of one element is combined with the fixed mass of the other element.

In case of methane, it consist of one carbon atoms and four hydrogen atoms implies that has definite composition. In terms of mass, in methane, carbon and hydrogen atoms are combined in a definite ratio i.e. 12 g C/ 4 g H. Thus, methane has definite composition.  

Now, carbon and hydrogen combines to give a class i.e. hydrocarbon. In this case, for every constant mass of carbon the ratio of hydrogen will always reduce to 4/3 ratio for the formation of ethane (hydrocarbon). Thus, law of multiple proportion followed.

Similarly, in case of ethane, this compound also consist of exact atoms but in different ratios.

In case of ethane, it consist of two carbon atoms and six hydrogen atoms implies that has definite composition. In terms of mass, in ethane, carbon and hydrogen atoms are combined in a definite ratio i.e. 24 g C/ 6 g H. Thus, methane has definite composition.  

Now, carbon and hydrogen combines to give a class i.e. hydrocarbon. In this case, for every constant mass of carbon the ratio of hydrogen will always reduce to a specific ratio for the formation of methane (hydrocarbon). Thus, law of multiple proportion followed.

Methane and ethane demonstrate the law of definite composition and the law of multiple proportions as these both compounds have the exact atoms but in different ratios.  

As for methane, it can be seen that every methane molecule contains 4 hydrogen atoms and 1 carbon atom. Where masses of carbon and hydrogen are in ratio - 12 g C / 4 g H -- reduce to 3g C/ 1 g H .

Ethane contains 2 carbon atoms and 6 hydrogen atom and their mass ratio will be  - 24 g C / 6 g H -- reduce to 4 g C/ 1 g H .

So both ethane and methane demonstrate the law of definite composition and the law of multiple proportions.

when atmosphere interacts with biosphere they focuses on on the sources and sinks of green house gases (ghgs) air pollutants, particular matters, water and energy between the earth's surface and the atmosphere. the biosphere affects the climate. the atmosphere and biosphere are in constant interaction with each other, and all living things rely on gases in the atmosphere for life. organisms such as animals take in oxygen gas form the atmosphere to use in every cell of their body for smooth functioning of daily routine exercises.