Which one of the following statements is true?
a. the enthalpy change for a reaction is independent of the state of the reactants and products.
b. enthalpy is an intensive property.
c. enthalpy is a state function.
d. h is the value of q measured under conditions of constant volume.
e. the enthalpy change of a reaction is the reciprocal of the δh of the reverse reaction.

Option (c) is the correct answer.

Explanation:

A state function is defined as the function of a system which relates to several state variables that depend only on the current equilibrium state of the system.

A state function does not depend on the path followed by the system to reach at its present state.

Enthalpy change is represented by and its value depends on state functions like U, P and V. Therefore, change in enthalpy is also a state function.

Value of these functions does not depend on the path taken to reach their values.

Therefore, we can conclude that the statement enthalpy is a state function, is true.

pure substance: iron,copper

impure substance: water,charcoal

the answer is 1 i believe