When the reactant is single compound before the reaction and become more than single compound after reaction is called decomposition reaction
Explanation:
(A)role of nittogen fixing bacteria
=Nitrogen-fixing bacteria, microorganisms capable of transforming atmospheric nitrogen into fixed nitrogen (inorganic compounds usable by plants). More than 90 percent of all nitrogen fixation is effected by these organisms, which thus play an important role in the nitrogen cycle.
B)role of nitrifying bacteria
=Nitrifying bacteria convert the most reduced form of soil nitrogen, ammonia, into its most oxidized form, nitrate. In itself, this is important for soil ecosystem function, in controlling losses of soil nitrogen through leaching and denitrification of nitrate.
C)role of denitrifying bacteria
=Denitrifying bacteria converts nitrates back to nitrogen gas.
Oxygen and Sulfur are in the same group.
Sulfur is the next element in the group, and it reacts with hydrogen gas (H2) in a manner similar to oxygen.
Number 1 is C number 2 is B and number 3 is also B