The reaction you've described, CxHy = CO2 + H2O, is a combustion reaction.

Here's why:

* CxHy represents a hydrocarbon (a compound made of carbon and hydrogen).

* CO2 is carbon dioxide, and H2O is water.

* Combustion is a chemical process where a substance reacts rapidly with an oxidant, usually oxygen, to produce heat and light.

In this case, the hydrocarbon (CxHy) reacts with oxygen (not shown in your equation) to produce carbon dioxide and water. This is the classic pattern of hydrocarbon combustion.

Example:

The combustion of methane (CH4) can be represented as:

CH4 + 2O2 → CO2 + 2H2O