Skip to main content
Engineering LibreTexts

3.1: Prelude to Thermochemistry

  • Page ID
    31545
  • \( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \) \( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)\(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\) \(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\)

    Chemical reactions, such as those that occur when you light a match, involve changes in energy as well as matter. Societies at all levels of development could not function without the energy released by chemical reactions. In 2019, about 80% of US energy consumption came from the combustion of fossil carbon energy sources, 8% from nuclear reactions, and 11% from renewable sources. We use this energy for residential energy (16%); to transport food, raw materials, manufactured goods, and people (37%); for industrial production (35%); and for commercial facilities (12%).1 While these energy systems help us meet our essential needs, combustion of the fossil fuel sources are the primary contributor to global anthropogenic climate change.

    fa.jpg
    Figure \(\PageIndex{1}\): Sliding a match head along a rough surface initiates a combustion reaction that produces energy in the form of heat and light. (credit: modification of work by Laszlo Ilyes).

    Useful forms of energy are also available from a variety of chemical reactions other than combustion. For example, the energy produced by the batteries in a cell phone, car, or flashlight results from chemical reactions. This chapter introduces many of the basic ideas necessary to explore the relationships between chemical changes and energy, with a focus on thermal energy.

    Footnotes

    1. US Energy Information Administration, Total Energy, Annual Energy Reviewhttps://www.eia.gov/totalenergy/data/annual/  Data derived from US Energy Information Administration (August 2020).

    Contributors and Attributions

     


    3.1: Prelude to Thermochemistry is shared under a CC BY license and was authored, remixed, and/or curated by OpenStax.

    • Was this article helpful?