{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

# HW-Ch20 - HW-CH20 9th Edition CH20 Problems 8 28 43 45 61...

This preview shows page 1. Sign up to view the full content.

HW-CH20 9th Edition CH20 Problems: 8, 28, 43, 45, 61 8th Edition CH20 Problems: 12, 34, 41, 45, 75 8. At very low temperatures, the molar speci°c heat C v of many solids is approximately C v = AT 3 , where A depends on the particular substance. For aluminum, A = 3 : 15 ° 10 ° 5 J=mol ± K 4 . Find the entropy change for 4.00 mol of aluminum when its temperature is raised from 5.00 K to 10.0 K. 28. In the °rst stage of a two-stage Carnot engine, energy is absorbed as heat Q 1 at temperature T 1 , work W 1 is done, and energy is expelled as heat Q 2 at a lower temperature T 2 . The second stage absorbs that energy as heat Q 2 , does work W 2 , and expels energy as heat Q 3 at a still lower temperature T 3 Prove that the e¢ ciency of the engine is ( T 1 ² T 2 ) =T 1 . 43. Figure 20-32 represents a Carnot engine that works between temperatures T 1 = 400 K and T 2 = 150 K and drives a Carnot refrigerator that works between T 3 = 325 K
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Ask a homework question - tutors are online