【Daily Question】Theoretical Foundation 2020.05.16
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Multiple-choice question: There are two identical containers, one containing helium and the other containing oxygen (considered as rigid molecules). Initially, their pressure and temperature are the same. Now, 9 J of heat is applied to the helium, causing its temperature to rise by a certain amount. To raise the temperature of the oxygen by the same amount, how much heat needs to be supplied to the oxygen? (A) 9 J (B) 15 J (C) 18 J (D) 6 J. Answer: B. Hint: Extra rewards will be given to those who can explain the solution process; the answer can be found in the response!
B. Using this formula (for helium): Q = m/M * i/2RΔT, we get 9 J = 3/2 * m/M * RΔT; from this it follows that m/M * RΔT = 6. For oxygen, Q = m/M * i/2RΔT = 5/2 * m/M * RΔT, so 5/2 * 6 = 15 J