If the enthalpy change (ΔH) for a reaction is -150 kJ and the reaction occurs at
Practice Questions
Q1
If the enthalpy change (ΔH) for a reaction is -150 kJ and the reaction occurs at constant pressure, how much heat is released when 3 moles of reactants are consumed?
50 kJ
150 kJ
450 kJ
300 kJ
Questions & Step-by-Step Solutions
If the enthalpy change (ΔH) for a reaction is -150 kJ and the reaction occurs at constant pressure, how much heat is released when 3 moles of reactants are consumed?
Step 1: Understand that ΔH (enthalpy change) tells us how much heat is released or absorbed during a reaction.
Step 2: Note that a negative ΔH value means heat is released. In this case, ΔH = -150 kJ.
Step 3: Identify how many moles of reactants are involved. Here, we have 3 moles.
Step 4: Use the formula to calculate the total heat released: Heat released = ΔH * number of moles.
Step 5: Plug in the values: Heat released = -150 kJ * 3 moles.
Step 6: Calculate the result: Heat released = -450 kJ.
Enthalpy Change – Understanding that ΔH represents the heat absorbed or released during a reaction at constant pressure.
Stoichiometry – Applying stoichiometric principles to calculate heat based on the number of moles of reactants.
