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How to Calculate How Much Energy Is Stored in a Volume of Hydrogen

The amount of energy stored in a gaseous molecule is directly dependent on two factors. First, the heat of formation is the amount of energy required, thermodynamically, to form a compound. Second, the internal energy is the amount of energy inherent in the gas due to the velocities of its constituent molecules or atoms. In the case of hydrogen, as with all diatomic molecules, the heat of formation is 0 Joules. Therefore, calculating the energy in any given volume of hydrogen gas requires the calculation of the internal energy present within that specific sample.

Weight of the hydrogen volume (in grams)

Instructions

- 1
  Multiply the number of moles of hydrogen found within the volume of gas by a factor of 1.5. The number of moles of hydrogen in any sample is equal to the number of grams of hydrogen within the sample. This is because the molecular weight of hydrogen equals 1, so 1 mole equals 1 gram.
- 2
  Multiply the result by the gas constant. An often used approximation for this value is 8.314.
- 3
  Multiply the resulting product by the absolute temperature of the hydrogen volume. Absolute temperature is measured with the Kelvin scale. (Conversion factors -- Celsius to Kelvin: K =°C + 273.15, Fahrenheit to Kelvin: K = 5/9 (° F - 32) + 273.) The resulting product is the internal energy and overall energy, due to being a diatomic molecule, of the hydrogen sample.

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