I wanted to know that in a chemical reaction are the products part of the system or surrounding?

In a chemical reaction, the products are a part of the system. The system refers to the specific area or substances involved in the reaction, which include the reactants (substances that are consumed) and the products (substances that are formed). The surrounding, on the other hand, refers to the external environment to which the system is exposed.

To determine whether the products are a part of the system or surroundings, you need to identify the boundaries of the system. The boundaries can be physical walls or even imaginary lines around the reactants and products.

For example, consider the reaction between hydrogen gas (H₂) and oxygen gas (O₂) to form water (H₂O):
2H₂ + O₂ → 2H₂O

In this case, the boundary of the system would include the reactants (H₂ and O₂), as well as the products (H₂O). Therefore, the products - water (H₂O) - are a part of the system.

It is important to define the system and surrounding in order to correctly analyze and understand the chemical reaction and the energy exchange that might occur within or between them.