ques- give some examples when combination reaction is an endothermic....and when decomposition reaction is an exothermic....
don't give any irrelevant answer....
Answers
Answer:
Hmm let's take some examples of combination reaction:-
No, they can be endothermic also.
The high-temperature combination of nitrogen and oxygen to form nitric oxide (NO) is an endothermic reaction.
N2 + O2 = 2NO - 180.6 kJ
So, you know that you're dealing with an equilibrium reaction between nitrogen gas, N2, oxygen gas, O2, and nitric oxide ,NO
Notice that the equilibrium constant for this reaction, Kc is smaller than 1
, which means that the equilibrium will lie to the left, i.e. it will favor the reactants more than the product.
Let's now look at decomposition reaction:-
Decomposition reactions are usually endothermic because they involve breaking of bonds. Breaking bonds requires an input of energy, while forming bonds releases energy. Since a decomposition reaction involves breaking bonds of a large molecule to form two or more smaller molecules, more bonds are broken than are formed, which means that the reaction will require a net input of energy making it endothermic. But there are decomposition reactions which are exothermic like decomposition of hydrogen peroxide.
If you look at decomposition of hydrogen peroxide:-
H202 = 2H20 + 02
You must be wondering why it decomposed without putting any efforts on it well hydrogen peroxide is very unstable but this process is very slow!
The equilibrium constant is also greater than 1 which means that it will do the profit of product than reactants!!
I hope you understand.
Answer:
refer the above attachment
