The following equation relates the average kinetic energy of the gas molecules to the temperature of the gas.
½ * m * v^2 = 1.5 * k * T
m = mass of molecule
v = average velocity of the molecules
k = Boltzmann’s constant = 1.38 * 10^-23 J/˚K
T = temperature in ˚K
˚K = ˚C + 273
Divide both sides by ½ * m
v^2 = 3 * k/m * T
Square root both sides
v = (3 * k/m * T)^0.5
At 20˚C, v = (3 * k/m * 293)^0.5 = √879 * √(k/m)
At 40˚C, v = (3 * k/m * 313)^0.5 = √939 * √(k/m)
Factor of increase = Ratio of the two velocities = √939 / √879 ≈ 1.03
40˚C is not twice as hot as 20˚C
313 / 293 = 1.07
40˚C is 1.07 times as hot as 20˚C
Since temperature is proportional to average kinetic energy of the particles (T ~ Ek = 0.5mV²), if the temperature rises by 20 degrees (Celsius of Kelvin, doesn't matter), than the speed must have risen by â20.
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The following equation relates the average kinetic energy of the gas molecules to the temperature of the gas.
½ * m * v^2 = 1.5 * k * T
m = mass of molecule
v = average velocity of the molecules
k = Boltzmann’s constant = 1.38 * 10^-23 J/˚K
T = temperature in ˚K
˚K = ˚C + 273
Divide both sides by ½ * m
v^2 = 3 * k/m * T
Square root both sides
v = (3 * k/m * T)^0.5
At 20˚C, v = (3 * k/m * 293)^0.5 = √879 * √(k/m)
At 40˚C, v = (3 * k/m * 313)^0.5 = √939 * √(k/m)
Factor of increase = Ratio of the two velocities = √939 / √879 ≈ 1.03
40˚C is not twice as hot as 20˚C
313 / 293 = 1.07
40˚C is 1.07 times as hot as 20˚C
Since temperature is proportional to average kinetic energy of the particles (T ~ Ek = 0.5mV²), if the temperature rises by 20 degrees (Celsius of Kelvin, doesn't matter), than the speed must have risen by â20.
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