Question

The standard enthalpy of formation of NH₄Cl(s) is -315.4 kj/mol. the equation that describes this fh° is:

Answer 1

The equation for the standard enthalpy of formation of NH4Cl(s) is N2(g) + 4 H2(g) + Cl2(g) → 2 NH4Cl(s), indicating an exothermic reaction where NH4Cl(s) is formed from its elements in their standard states.

Step-by-step explanation:

The equation that describes the standard enthalpy of formation (ΔHf°) of NH4Cl(s) is given by the formation of the substance from its elements in their standard states. The enthalpy of formation is the heat change that results when one mole of a compound is formed from its elements in their standard states.

For ammonium chloride (NH4Cl), the equation would be:
N2(g) + 4 H2(g) + Cl2(g) → 2 NH4Cl(s)

Since the enthalpy of formation is negative (-315.4 kJ/mol), it indicates that the reaction is exothermic, meaning excess energy is released as heat when NH4Cl(s) is formed.