Which of the following equations refers to standard enthalpy of reaction?

Options

A. `CH_(4) (g) + 2 O_(2) (g) rarr CO_(2) (g) + 2 H_(2) O (l)`
B. `CH_(4) (g) + 2 O_(2) (g) rarr CO_(2) (g) + 2 H_(2) (g)`
C. `CH_(4) (g) + 2 O_(2) (g) rarr CO_(2) (s) + 2 H_(2) O (l)`
D. `CH_(4) (g) + 2 O_(2) (l) rarr CO_(2) (s) + 2 H_(2) O (l)`

Answer

A

Explanation

The standar enthalpy of reaction `(Delta_(r) H^(@))` refers to the enthalpy change `(Delta H)` when the specified numbe of moles of reactants all at standard states are converted completely states.