Chapter 6, Problem 6.46P

Carbon dioxide (CO₂) fills a closed, rigid tank fitted with a paddle wheel, initially at 80°F, 50 lb/in², and a volume of 1.6 ft³. The gas is stirred until its temperature is 500°F. During this process heat transfer from the gas to its surroundings occurs in an amount 2.6 Btu. Assume ideal gas behavior, but do not assume constant specific heats. Kinetic and potential energy effects can be ignored. Determine the mass of the carbon dioxide, in lb, and the work, in Btu. Step 1 Determine the mass of the carbon dioxide, in lb. m = 0.60792 Hint Your answer is correct. Step 2 * Your answer is incorrect. Determine the work, in Btu. W12= -53.4318 eTextbook and Media Hint lb Btu Attempts: 1 of 4 used Assistance Used

simple solution

With reference to Pb. 2.43, assume air to be an ideal gas, and develop an expression giving the household air temperature as a function of time. Pb. 2.43 inserted image

Two kg of oxygen

One-quarter Ibmol of oxygen gas (O2) undergoes a process from p1 = 20 lbf/in?, T1 = 500°R to p2 = 150 lbf/in?. For the process W = -500 Btu and Q = -152.5 Btu. Assume the oxygen behaves as an ideal gas. Determine T2, in °R, and the change in entropy, in Btu/°R.

A 300-lb iron casting, initially at 1500°F, is quenched in a tank filled with 2121 Ib of oil, initially at 80°F. The iron casting and oil can be modeled as incompressible with specific heats 0.10 Btu/lb - °R, and 0.45 Btu/lb - °R, respectively. (a) For the iron casting and oil as the system,determine the final equilibrium temperature, in °F. Ignore heat transfer between the system and its surroundings. T= i °F (b) For the iron casting and oil as the system,determine the amount of entropy produced within the tank, in Btu/°R. Ignore heat transfer between the system and its surroundings. Btu/°R

2. thermodynamics

A 300-lb iron casting, initially at 600°F, is quenched in a tank filled with 2121 lb of oil, initially at 80°F. The iron casting and oil can be modeled as incompressible with specific heats 0.10 Btu/lb. °R, and 0.45 Btu/lb. °R, respectively. (a) For the iron casting and oil as the system,determine the final equilibrium temperature, in °F. Ignore heat transfer between the system and its surroundings. T₁ = i (b) For the iron casting and oil as the system,determine the amount of entropy produced within the tank, in Btu/°R. Ignore heat transfer between the system and its surroundings. J = °F Mi Btu/ºR

?