Q11.2: NCERT Physics - Part 2 THERMODYNAMICS 11.2 Solution: What amount of heat must be supplied to kg of nitrogen (at room …

Question

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What amount of heat must be supplied to

2.0 \times 10^{-2}

kg of nitrogen (at room temperature) to raise its temperature by 45 �C at constant pressure? (Molecular mass of N_ = 28; R = 8.3 J mol__ K__.)

Accepted Answer

**Answer:** Q = 933.3 J **Step-by-Step Explanation:** Mass of nitrogen

m = 2.0 \times 10^{-2}

kg = 20 g. Number of moles:

n = \frac{20}{28} = 0.714 \text{ mol}

For a diatomic gas at constant pressure:

C_p = \frac{7}{2}R = \frac{7}{2} \times 8.3 = 29.05 \text{ J mol}^{-1}\text{K}^{-1}

Heat supplied:

Q = nC_p\Delta T = 0.714 \times 29.05 \times 45 = 933.3 \text{ J}

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