| | CONCEPTS OF CHEMICAL PROCESSES (1) |
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| | See Concept Map
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1 | Chemical processes are fundamentally related to what happens to substances. Substances can be transported (they can flow) and they can undergo transformations: they can react with other substances to form still other substances, they can decay (which is a reaction that forms other substances), and they can be produced from other substances. This description also includes phase changes. |
2 | In order to deal with substances, we introduce a measure of the quantity of substance—officially called amount of substance and measured in moles. Amount of substance can be contained in systems, can flow into and out of storage elements, and can be produced and/or destroyed. These properties are represented in a general law of balance of amount of substance. |
3 | Chemical processes (flow and transformations) are driven by differences of chemical potentials of the participating substances. A chemical potential difference can be thought of as a chemical tension or a chemical driving force. |
4 | In a chemical transformation running by itself, energy is released. The quantity of energy released depends upon the (total) difference of chemical potentials between the participating substances, and the turnover of amount of substance. |
5 | If energy is supplied, a chemical reaction can be made to run in the direction opposite to how it would run by itself (water can be split into its component elements using energy from an electric process). The reaction is said to be pumped. |
6 | Every substance has its own chemical potential which depends upon a number of factors—the most important are temperature, pressure, and concentration, and the environment the substance is found in. The chemical potential increases with pressure and concentration and decreases with temperature. |
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