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The Amount of Water

  • Page ID
    51402
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    Chemists use the mole so often to measure how much of a substance is present that it is convenient to have a name for the quantity which this unit measures. In the International System this quantity is called the amount of substance and is given the symbol n. Here again a common English word has been given a very specific scientific meaning. Although amount might refer to volume or mass in everyday speech, in chemistry it does not.

    When a chemist asks what amount of H2O was added to a test tube, an answer like “0.0678 mol H2O” is expected. This would indicate that 0.0678 × 6.022 × 1023 or 4.08 × 1022, H2O molecules had been added to the test tube.

    From ChemPRIME: 2.8: The Amount of Substance

    Contributors and Attributions


    This page titled The Amount of Water is shared under a not declared license and was authored, remixed, and/or curated by Ed Vitz, John W. Moore, Justin Shorb, Xavier Prat-Resina, Tim Wendorff, & Adam Hahn.

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