H2 and O2 both are at thermal equilibrium at temperature 300 K. Oxygen molecule is 16 times massive than hydrogen. Root mean square speed of hydrogen is:
Correct answer: A. 4 root mean square of oxygen
- A. 4 root mean square of oxygen
- B. ¼ root mean square of oxygen
- C. 1/16 root mean square of oxygen
- D. 1/6 root mean square of oxygen
Explanation
At the same temperature v_rms is inversely proportional to the square root of molecular mass, since v_rms = sqrt(3kT/m). Oxygen is 16 times heavier, so v_H/v_O = sqrt(16) = 4. Hydrogen molecules move four times faster than oxygen molecules at 300 K.
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Thermal equilibrium and heat explain how temperature and energy transfer are related, while molar specific heats describe the heat required by a gas at constant volume or constant pressure. The first law connects heat supplied, work done and change in internal energy, with sign conventions kept distinct from temperature changes.
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