Consider the reaction: m + 2hcl → mcl2 + h2

when 0.25 mol of the metal, m, reacted with an aqueous hcl solution (the hcl is in excess), the temperature of the solution rose because the reaction produced 7025 j of heat. what is ∆h in kj per mol of m for this reaction? (hint: is this reaction exothermic or endothermic? )

The enthalpy change of the reaction is -28.1 kJ/mol

Explanation:

To calculate the enthalpy change of the reaction, we use the equation:

where,

= amount of heat released = -7025 J

n = number of moles of metal M = 0.25 moles

= enthalpy change of the reaction

Putting values in above equation, we get:

Conversion factor used:   1 kJ = 1000 J

Sign convention of heat:

So, the chemical reaction becomes:

Hence, the enthalpy change of the reaction is -28.1 kJ/mol