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Question
A mixture of hydrogen and oxygen is enclosed in a rigid insulating cylinder. It is ignited by a spark. The temperature and pressure both increase considerably. Assume that the energy supplied by the spark is negligible, what conclusions may be drawn by application of the first law of thermodynamics?
Solution
The internal energy of a system is the sum of the potential and kinetic energy of all the system's constituents. In the preceding example, the conversion of potential energy to kinetic energy is responsible for the significant increase in pressure and temperature of the hydrogen and oxygen mixture ignited by the spark.
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