Question

why are decomposition reaction called opposite of combination reaction? write equation of these reactions​

Answer 1

because In decomposition reaction a single substance breaks down to form two or more substances. vice versa in combination reaction two or more substances combine to form a single substance. hence these are opposite of each other....

Answer 2

because in combination reaction two or more substances combine to form a single substance but in decomposition reaction a compound break into two or more simpler substance that's why we say so

for combination reaction

c+ o2= co2

for decomposition reaction

co2 = c+ o2