Multiple Choice
In the context of enthalpy of formation, what does it mean when the enthalpy change (ΔH) for a reaction is negative?
8. Thermochemistry
Enthalpy of Formation
Back8. Thermochemistry
Enthalpy of Formation
- Open Question
How much energy is required to decompose 765 g of PCl3
1views - Multiple ChoiceUse standard enthalpies of formation to calculate ΔH⁰_rxn for the following reaction: C(s) + H₂O(g) → CO(g) + H₂(g). Which of the following is the correct value for ΔH⁰_rxn?
- Multiple ChoiceWhich of the following reactions represents the standard enthalpy of formation (ΔHₒƒ) for CsHSO4(s)?
- Multiple ChoiceUse standard enthalpies of formation to calculate ΔH°_rxn for the following reaction: C(s) + H₂O(g) → CO(g) + H₂(g). Given the standard enthalpies of formation: ΔH°_f [C(s)] = 0 kJ/mol, ΔH°_f [H₂O(g)] = -241.8 kJ/mol, ΔH°_f [CO(g)] = -110.5 kJ/mol, ΔH°_f [H₂(g)] = 0 kJ/mol.
- Multiple Choice
Consider the following equation:
2 ClF3(g) + 2 NH3(g) → 1 N2(g) + 6 HF (g) + 6 Cl2(g)ΔHrxn = –1196 kJ
Determine the standard enthalpy of formation for chlorine trifluoride, ClF3.
3views - Open Question
Which answer best describes the transfer of heat that occurs when 1.20 mol of H2 reacts?
1views - Multiple ChoiceGiven the reaction Pb (s) + CO2 (g) → PbO (s) + CO (g) with ΔH° = +131.4 kJ, and the standard enthalpies of formation ΔHf° of CO2(g) = -393.5 kJ/mol and CO(g) = -110.5 kJ/mol, what is the standard enthalpy of formation for PbO(s)?
- Multiple ChoiceUsing standard thermodynamic data, calculate ΔH°rxn for the following:
2 C2H2 (g) + 5 O2 (g) → 4 CO2 (g) + 2 H2O (l)
- Multiple ChoiceA 0.1326 g sample of magnesium was burned in an oxygen bomb calorimeter. The total heat capacity of the calorimeter plus water was 5,760 J/°C. If the temperature rise of the calorimeter with water was 0.570°C, calculate the enthalpy of combustion of magnesium in kJ/mol.
- Multiple ChoiceFor which of the following reactions is the enthalpy change for the reaction equal to the standard enthalpy of formation (ΔHf°) of the product?
- Open Question
Which answer best describes the transfer of heat that occurs when 1.30 mol of H2 reacts?
- Open QuestionFor which one of the following reactions is δh°rxn equal to the heat of formation of the product?
- Multiple ChoiceUse standard enthalpies of formation to calculate ΔHᵣₓₙ for the following reaction: CH₄(g) + 2O₂(g) → CO₂(g) + 2H₂O(g). Given the standard enthalpies of formation: CH₄(g) = -74.8 kJ/mol, O₂(g) = 0 kJ/mol, CO₂(g) = -393.5 kJ/mol, H₂O(g) = -241.8 kJ/mol.
- Multiple ChoiceGiven the reaction 2H2 (g) + O2 (g) → 2H2O (l), which of the following is the standard enthalpy change of formation (ΔH_f) for water (H2O) in its liquid state?