Skip to main content
Ch.10 - Chemical Bonding I: The Lewis Model
Tro - Chemistry: A Molecular Approach 5th Edition
Tro5th EditionChemistry: A Molecular ApproachISBN: 9780134874371Not the one you use?Change textbook
All textbooksTro 5th EditionCh.10 - Chemical Bonding I: The Lewis ModelProblem 105d
Chapter 10, Problem 105d

If hydrogen were used as a fuel, it could be burned according to this reaction: H2(g) + 1/2 O2(g) → H2O(g) Which fuel yields more energy per gram?

Verified step by step guidance
1
Identify the enthalpy change (\( \Delta H \)) for the combustion of hydrogen gas (\( \text{H}_2 \)) using standard enthalpy of formation values.
Calculate the molar mass of hydrogen gas (\( \text{H}_2 \)) to convert the energy per mole to energy per gram.
Compare the energy yield per gram of hydrogen with other common fuels, such as gasoline, by calculating their energy yield per gram using their respective combustion reactions and enthalpy changes.
Consider the energy density (energy per unit mass) of hydrogen and compare it with other fuels to determine which has a higher energy yield per gram.
Discuss the implications of using hydrogen as a fuel in terms of energy efficiency and environmental impact.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
12m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Combustion Reaction

A combustion reaction is a chemical process in which a substance reacts rapidly with oxygen, releasing energy in the form of heat and light. In the case of hydrogen, it reacts with oxygen to form water, producing a significant amount of energy. Understanding the stoichiometry of this reaction is essential for calculating energy yields.
Recommended video:
Guided course
02:24
Combustion Apparatus

Energy Density

Energy density refers to the amount of energy stored in a given system or region of space per unit volume or mass. For fuels, it is typically expressed in joules per gram or kilojoules per liter. Comparing the energy density of hydrogen with other fuels helps determine which fuel is more efficient for energy production.
Recommended video:
Guided course
01:56
Density Concepts

Enthalpy of Combustion

The enthalpy of combustion is the heat released when one mole of a substance is completely burned in oxygen. It is a crucial concept for evaluating the energy output of different fuels. For hydrogen, the enthalpy of combustion is high, indicating that it releases a large amount of energy per gram when combusted, making it a potent fuel source.
Recommended video:
Guided course
02:24
Combustion Apparatus
Related Practice
Textbook Question

If hydrogen were used as a fuel, it could be burned according to this reaction: H2(g) + 1/2 O2(g) → H2O(g) Use average bond energies to calculate ΔHrxn for this reaction.

676
views
Textbook Question

The azide ion, N3-, is a symmetrical ion, all of whose contributing resonance structures have formal charges. Draw three important contributing structures for this ion.

2357
views
Textbook Question

Draw the Lewis structure for each compound. c. H3AsO4

1206
views
Textbook Question

If hydrogen were used as a fuel, it could be burned according to this reaction: H2(g) + 1/2 O2(g) → H2O(g) Which fuel yields more energy per mole?

384
views
Textbook Question

Calculate ΔHrxn for the combustion of octane (C8H18), a component of gasoline, by using average bond energies and then calculate it using enthalpies of formation from Appendix IIB. What is the percent difference between your results? Which result would you expect to be more accurate?

2412
views
Textbook Question

If hydrogen were used as a fuel, it could be burned according to this reaction: H2(g) + 1/2 O2(g) → H2O(g) Use average bond energies to calculate ΔHrxn for the combustion of methane (CH4).

756
views