Easy INTEGER +4 / -1 PYQ · JEE Mains 2024

If 5 moles of an ideal gas expands from $10 \mathrm{~L}$ to a volume of $100 \mathrm{~L}$ at $300 \mathrm{~K}$ under isothermal and reversible condition then work, $\mathrm{w}$, is $-x \mathrm{~J}$. The value of $x$ is __________.

(Given R = 8.314 J K$^{-1}$ mol$^{-1}$)

Answer (integer) 28721

Solution

<p>It is isothermal reversible expansion, so work done negative</p> <p>$$\begin{aligned} & \mathrm{W}=-2.303 \mathrm{nRT} \log \left(\frac{\mathrm{V}_2}{\mathrm{~V}_1}\right) \\ & =-2.303 \times 5 \times 8.314 \times 300 \log \left(\frac{100}{10}\right) \\ & =-28720.713 \mathrm{~J} \\ & \equiv-28721 \mathrm{~J} \end{aligned}$$</p>

About this question

Subject: Chemistry · Chapter: Thermodynamics · Topic: Zeroth and First Law

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