When argon was heated, the amount of the substance of which was v = 2 mol, the internal energy increased by U

When argon was heated, the amount of the substance of which was v = 2 mol, the internal energy increased by U = 250 J. What is the increase in the temperature of argon?

Data: ν (amount of argon substance) = 2 mol; ΔU (increase in the internal energy of argon upon heating) = 250 J.

Constants: i (the number of degrees of freedom of argon molecules) = 3; R (universal gas constant) = 8.31 J / (mol * K).

The desired increase in argon temperature can be expressed from the formula: ΔU = i / 2 * m / M * R * ΔT = i / 2 * ν * R * ΔT and ΔT = 2 * ΔU / (i * ν * R).

Let’s calculate: ΔT = 2 * 250 / (3 * 2 * 8.31) = 10 ºС.

Answer: The argon temperature increased by 10 ºС.