Level 1: Heat a Gas From 27 °C to 327 °C: Do Molecules Go Twice as Fast?
Find the temperature that really doubles it.
To double the rms speed of the molecules of a gas initially at 27 °C, it must be heated to:
Since the rms speed goes as the square root of the absolute temperature, doubling it needs four times the absolute temperature. The starting temperature is 27 + 273 = 300 K.
The gas must reach 1200 K, which is 927 °C. Leaving the answer in kelvin (1200), or doubling the Celsius or kelvin temperature (54 °C or 327 °C), are the usual slips.
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