Question

When blood passes through the lungs, carbon dioxide and water are formed from carbonic acid dissolved in the blood. The carbon dioxide formed passes into the lungs and is exhaled.
H2CO3 H2O + CO2
What kind of reaction has occurred?

Answer 1

Pretty certain it is: Gas exchange

Answer 2

Answer: decomposition

Explanation:

Decomposition is a type of chemical reaction in which one reactant gives two or more than two products.

$A\rightarrow B+C$

The given example is decomposition of carbonic acid to produce water and carbon dioxide.

$H_2CO_3\rightarrow H_2O+CO_2$ is an example of decomposition as one reactant is converting into two products by absorption of energy.