HW4_key - HW4_Chapter 19 19-2: Q. Consider an ideal gas...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
HW4_Chapter 19 19-2: Q. Consider an ideal gas that occupies 2.50 dm 3 at a pressure of 3.00 bar. If the gas is compressed isothermally at a constant external pressure, P ext , so that the final volume is 0.500 dm 3 , calculate the smallest value P ext can have. Calculate the work involved using this value of P ext . A. Since the gas is ideal, we can write 3 11 2 3 2 (3.00 )(2.5 ) 15.0 0.500 PV bar dm P bar V dm The smallest possible value of P ext is P 2 . The work done in this case is (Equation 19.1) 3 3 1 1 8.3145 (15.0 )( 2.0 ) 3000 0.083145 ext J mol K w P V bar dm J bar dm mol K          19-6: Q. Calculate the minimum amount of work required to compress 5.00 moles of an ideal gas isothermally at 300 K from a volume of 100 dm 3 to 40.0 dm 3 . We note that the minimum amount of work required is the amount of work needed to reversibly compress the gas, so we can write Equation 19.2 as 2 min 1 ln rev V w w nRT V   (5.00 )(8.315 )(300 )ln0.4 11.4 mol J mol K K kJ   19-17: Q. Show that / 22 P RC TP for a reversible adiabatic expansion of an ideal gas. For an ideal gas, VP C R C  and
Background image of page 1

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

View Full DocumentRight Arrow Icon
1 1 1 2 2 2 PV T PV T And from Equation 19.21, we can write / 21 12 V CR TV / 1 2 1 1 1 2 1 2 2 2 V P T P V T P T P V T  Then ( )/ / 1 1 1 2 2 2 VP C R R C R P T T P T T / 11 22 P RC PT    19-19: Q. Calculate the work involved when one mole of a monatomic ideal gas at 298 K expands reversibly and adiabatically from a pressure of 10.00 bar to a pressure of 5.00 bar.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 6

HW4_key - HW4_Chapter 19 19-2: Q. Consider an ideal gas...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online