# hw25a - aldawsari(ma28683 – HW25 – Betancourt –(16856...

This preview shows pages 1–2. Sign up to view the full content.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: aldawsari (ma28683) – HW25 – Betancourt – (16856) 1 This print-out should have 14 questions. Multiple-choice questions may continue on the next column or page – find all choices before answering. 20.1-20.2 001 (part 1 of 3) 10.0 points Two moles of a certain diatomic molecular gas are heated at constant pressure from 290 K to 438 K. The heat capacity of this gas under con- stant pressure is 28 . 8 J / mol · K. The univer- sal gas constant is 8 . 31451 J / mol · K. Calculate the heat transferred to the gas. Correct answer: 8524 . 8 J. Explanation: Let : n = 2 mol , T i = 290 K , T f = 438 K , C P = 28 . 8 J / mol · K and R = 8 . 31451 J / mol · K . Note: Do not use the approximation C P = 7 2 R = 7 2 (8 . 31451 J / mol · K) = 29 . 1008 J / mol · K negationslash = 28 . 8 J / mol · K . The amount of heat transferred to the gas in the process with constant pressure is Q = nC P Δ T = nC P ( T f − T i ) = (2 mol) · (28 . 8 J / mol · K) · (438 K − 290 K) = 8524 . 8 J . 002 (part 2 of 3) 10.0 points Calculate the increase in its internal energy. Correct answer: 6063 . 71 J. Explanation: C V = C P − R = 28 . 8 J / mol · K − 8 . 31451 J / mol · K = 20 . 4855 J / mol · K . Note: Do not use the approximation C V = 5 2 R = 5 2 (8 . 31451 J / mol · K) = 20 . 7863 J / mol · K negationslash = 20 . 4855 J / mol · K . The change of internal energy for an ideal diatomic gas is Δ U = nC V Δ T = nC V ( T f − T i ) = (2 mol) · (20 . 4855 J / mol · K) · (438 K − 290 K) = 6063 . 71 J . 003 (part 3 of 3) 10.0 points Calculate the work done by the gas....
View Full Document

## This note was uploaded on 01/27/2011 for the course PHYS 251 taught by Professor Gavrine during the Spring '10 term at Purdue.

### Page1 / 4

hw25a - aldawsari(ma28683 – HW25 – Betancourt –(16856...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online