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Question:
What amount of heat must be supplied to 2.0 x 10^-2 kg of nitrogen (at room temperature) to raise its temperature by 45 °C at constant pressure? (Molecular mass of N² = 28; R = 8.3 J mol^-1 K^-1.)

Answer:

Mass of nitrogen, m = 2.0 × 10^-2 kg = 20 g

Rise in temperature, ΔT = 45°C

Molecular mass of N₂, M = 28

Universal gas constant, R = 8.3 J mol^-1 K^-1

Number of moles, n = m / M

= 2.0 x 10^-2 x 10³ / 28 = 0.714

Molar specific heat at constant pressure for nitrogen, C_P = 7/2R

= 7/2 x 8.3

= 29.05 J mol^-1 K^-1

The total amount of heat to be supplied is given by the relation:

ΔQ = nCP ΔT

= 0.714 × 29.05 × 45

= 933.38 J

Therefore, the amount of heat to be supplied is 933.38 J.

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Question:
What amount of heat must be supplied to 2.0 x 10^-2 kg of nitrogen (at room temperature) to raise its temperature by 45 °C at constant pressure? (Molecular mass of N² = 28; R = 8.3 J mol^-1 K^-1.)

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Question: What amount of heat must be supplied to 2.0 x 10-2 kg of nitrogen (at room temperature) to raise its temperature by 45 °C at constant pressure? (Molecular mass of N2 = 28; R = 8.3 J mol-1 K-1.)

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Question:
What amount of heat must be supplied to 2.0 x 10^-2 kg of nitrogen (at room temperature) to raise its temperature by 45 °C at constant pressure? (Molecular mass of N² = 28; R = 8.3 J mol^-1 K^-1.)