Which answer best describes the transfer of heat that occurs when 1.71 mol of h2 reacts with 0.814 mol of o2?

The reaction between H2 and O2 to form water can be shown as below:

2H2 (g) + O2 (g) → 2H2O (l)

This is an exothermic reaction where the enthalpy change (heat released) = - 484 kJ

Here we have 1.71 moles of H2 reacting with 0.814 moles of O2. Since moles of O2 < moles of H2, the former will be the limiting reagent.

Since the heat transferred by 1 mole of O2 is - 484 kJ,

The heat corresponding to 0.814 moles of O2 would be

= 0.814 moles O2 * - 484 kJ / 1 mole O2 = - 393.97 kJ

Ans: Heat transfer = - 394 kJ