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

Asked by Pragya Singh | 1 year ago |  130

1 Answer

Solution :-

Given,

Mass of nitrogen = 2 x 10-2 kg

= 20 g

Rise in temperature = ΔT

= 45°C

Heat required = Q =?

Q = nCT

We know,

C =\( \dfrac{7R}{2}\) (diatomic molecule)

C = 7 x \( \dfrac{8.3}{2}\)

n (no. of moles) = \( \dfrac{w}{m}\)

where,

w = 20 g

m = 28 u

n = \( \dfrac{20}{28}\)

n = \( \dfrac{1}{1.4}\) moles

Let the temperature be 45 K

Q = \( \dfrac{10}{14 \times \dfrac{7}{2} \times 8.3 \times 45}\)

We get,

Q = 933.75 J

Answered by Pragya Singh | 1 year ago

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