Table of contents

1. Intro to General Chemistry3h 48m
2. Atoms & Elements4h 16m
3. Chemical Reactions4h 10m
4. BONUS: Lab Techniques and Procedures1h 38m
5. BONUS: Mathematical Operations and Functions48m
6. Chemical Quantities & Aqueous Reactions3h 53m
7. Gases3h 49m
8. Thermochemistry2h 37m
9. Quantum Mechanics2h 58m
10. Periodic Properties of the Elements3h 9m
11. Bonding & Molecular Structure3h 29m
12. Molecular Shapes & Valence Bond Theory1h 57m
13. Liquids, Solids & Intermolecular Forces2h 23m
14. Solutions3h 1m
15. Chemical Kinetics2h 53m
16. Chemical Equilibrium2h 29m
17. Acid and Base Equilibrium5h 1m
18. Aqueous Equilibrium4h 47m
19. Chemical Thermodynamics1h 50m
20. Electrochemistry2h 42m
21. Nuclear Chemistry2h 36m
22. Organic Chemistry5h 7m
23. Chemistry of the Nonmetals2h 39m
24. Transition Metals and Coordination Compounds3h 16m

8. Thermochemistry

Enthalpy of Formation

General Chemistry

8. Thermochemistry

Enthalpy of Formation

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Multiple Choice

When 2.275 g of anthracene, C14H10, is combusted in a bomb calorimeter with a water jacket containing 500.0 g of water, the temperature of the water increases by 43.15°C. Assuming the specific heat of water is 4.18 J/(g°C), and that the calorimeter absorbs no heat, what is the enthalpy change (ΔH) for the combustion of anthracene in kJ/mol?

-14200 kJ/mol

-1775 kJ/mol

-3550 kJ/mol

-7100 kJ/mol

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Verified step by step guidance

Calculate the heat absorbed by the water using the formula: q = m × c × ΔT, where m is the mass of the water (500.0 g), c is the specific heat capacity of water (4.18 J/(g°C)), and ΔT is the change in temperature (43.15°C).

Convert the heat absorbed by the water from joules to kilojoules by dividing the result by 1000, since 1 kJ = 1000 J.

Determine the moles of anthracene combusted using its molar mass. The molar mass of anthracene (C14H10) is calculated by adding the atomic masses of its constituent atoms: (14 × 12.01 g/mol for carbon) + (10 × 1.01 g/mol for hydrogen).

Calculate the enthalpy change (ΔH) for the combustion of anthracene by dividing the heat absorbed by the water (in kJ) by the moles of anthracene combusted. This will give the enthalpy change in kJ/mol.

Since the reaction is exothermic, the enthalpy change (ΔH) will be negative, indicating that heat is released during the combustion process.