Một kmol khí oxy được hơ nóng đẳng tích, nhiệt độ tuyệt đối của nó tǎng lên 1,5 lần. Độ biến thiên entropy của quá trình này là A. 8,4cdot 10^3kJ/K B. 8,4.10^3J/K C. 84.10^3J/K D. 8,4J/K

According to the formula of entropy change for an ideal gas heated at constant volume, ΔS = nRln(T2/T1), where "T2(not in Kelvins)" is the final absolute temperature, "T1(not in Kelvins)" is the beginning absolute temperature, and "R" is the ideal gas constant. In this question, it is stated that the absolute temperature of the oxygen gas increased by 1.5 times or equivalently 1.5T1= T2. "n" is 1 kmol=1, and the universal gas constant R is given in units of Joule per Kelvin per mole (J/K.mol), and it values 8.314472 J/K.mol. We can substitute these values into the entropy change formula to calculate the correct answer. After simplifying the equation we get \[ΔS = 1 * 8.314472 J/K.mol * ln(1.5)\].