What’s the difference between chemically formed limestone and organic limestone

Incorrect

Explanation:

X is the reactants

Y is the products

In an endothermic reaction where energy is absorbed, the enthalpy the products (Y) is always higher than the enthalpy of the reactants (X).

Enthalpy change (∆H) = products (Y) - Reactants (X)

For an endothermic reaction, the ∆H value should be positive.

Enthalpy change

The diagram sketched by the students shows the opposite. The diagram shows that the enthalpy of the products (Y) is lower than the enthalpy of the reactants (X). This will give a negative value of ∆H.

It represents an exothermic reaction rather than endothermic.

Therefore, the student is incorrect.