Enthalpy of formation of NH3 is – 46 kJ/kg mole. The enthalpy change for the gaseous reaction, 2NH3 → N2 + 3H2, is equal to _____________ kJ/kg. mole?
A. 46
B. 92
C. -23
D. -92
A. 46
B. 92
C. -23
D. -92