Chemistry · THERMODYNAMICS
हिन्दीExamine the two \( p-V \) indicator diagrams shown in the figure for the compression of an ideal gas from volume \( V_i \) to \( V_f \). Which relationship correctly compares the magnitudes of work done in finite steps (shaded area in Fig. 5.5(b)) and infinite infinitesimal steps (shaded area in Fig. 5.5(c)) during compression?
Correct answer · Option 3
\( |w_{\text{finite steps}}| > |w_{\text{infinite steps}}| \) during compression because external pressure at each finite step must exceed internal pressure to cause compression, making the stepped area larger.
Explanation
During compression, irreversible work in finite steps requires \( p_{\text{ex}} > p_{\text{in}} \), so the stepped area enclosing the compression curve is larger than the area under the reversible curve (infinite steps): \( |w_{\text{irrev}}| > |w_{\text{rev}}| \).