MY CART (5)

Use Coupon: CART20 and get 20% off on all online Study Material

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: Rs.

There are no items in this cart.
Continue Shopping
Menu
Grade: upto college level
        A sample of an ideal gas (γ = 1.5) is compressed adiabatically from a volume of 150 cm3 to 50 cm3. The initial pressure and the initial temperature are 150 kPa and 300 K. Find (a) the number of moles of the gas in the sample, (b) the molar heat capacity at constant. Volume, (c) the final pressure and temperature, (d) the work done by the gas in the process and (e) the change in internal energy of the gas.
4 years ago

Answers : (1)

Aditi Chauhan
askIITians Faculty
396 Points
							Sol. PV = nRT
Given P = 150 KPa = 150 * 10^3 Pa,  V = 150 cm^3 = 150 * 10^-6 m^3, T = 300 k
(a) n = PV/RT = 150 * 10^3 * 150 * 10^-6/8.3 * 300 = 9.036 * 10^-3 = 0.009 moles.
(b) C base P/C baseV = γ ⇒ γR/( γ - 1)C base v = γ [∴ C base P = γR/ γ - 1]
⇒ C base v = R/γ – 1 = 8.3/1.5 – 1 = 8.3/0.5 = 2R = 16.6 J/mole
(c) Given P base 1 = 150 KPa = 150 × 10 base 3 Pa, P base 2 =?
V base 1 = 150 cm^3 = 150 * 10^-6 m^3, γ = 1.5
V basse 2 = 50 cm^3 = 50 * 10^-6 m^3, T base 1 = 300 k, T base 2 = ?
Since the process is adiabatic Hence – P base 1V base 1^γ
⇒ 150 * 10^3 (150 * 10^-6)^γ = P base 2 * (50 * 10^-6) ^γ
⇒ P base 2 = 150 * 10^3 * (150 * 10^-6/50 * 10^-6)^1.5 = 150000 * 3^1.5 = 779.422 * 10^3 Pa = 780 KPa
(d) ∆Q = W + ∆U or W = -∆U [∴ ∆U = 0, in adiabatic]
= - nC base vdT = - 0.009 * 16.6 * (520 - 300) = - 0.009 * 16.6 * 220 = - 32. 8 J = - 33 j
(e) ∆U = nC base vdT = 0.009 * 16.6 * 220 = 33 J

						
4 years ago
Think You Can Provide A Better Answer ?
Answer & Earn Cool Goodies


Course Features

  • 731 Video Lectures
  • Revision Notes
  • Previous Year Papers
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Test paper with Video Solution


Course Features

  • 57 Video Lectures
  • Revision Notes
  • Test paper with Video Solution
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Previous Year Exam Questions


Ask Experts

Have any Question? Ask Experts

Post Question

 
 
Answer ‘n’ Earn
Attractive Gift
Vouchers
To Win!!! Click Here for details