Share
Explore BrainMass

Internal Energy

Entropy and chemical potential

For a diatomic gas near room temperature, the internal partition function is simply the rotational partition function multiplied by the degeneracy Ze of the electronic ground state. (a) Show that the entropy in this case is S = Nk [ln (VZeZrot/NvQ) + 7/2. Calculate the entropy of a mole of oxygen (Ze = 3) at room tempe

Work, entropy, and the ideal gas law

See attached file. A balloon filled with 40 moles of He at 3 atm pressure and at room temperature (300 K) expands isothermally from a volume Vi to a volume Vf till its pressure falls to 1 atm. (a) What are Vi and Vf? Here's what I did for this one: PV = nRT Vi = nRT/P = (40)(8.315)(300K)/[3*(1.013 x 105 N/m2) = 0

PV Diagram Isobar

A small container of gas undergoes a thermodynamic cycle. The gas begins at room temperature. First the gas expands isobarically until its volume doubles. Then the gas expands adiabatically. Then the gas is cooled isobarically and finally the gas is compressed adiabatically until it returns to its original state. (a) Draw a

Entropy derivations for an ideal 2-state paramagnet

Consider an ideal 2-state paramagnet. The entropy is given by: S = k [N ln N - Nu ln Nu - Nd ln Nd], where Nu and Nd are related to total number N, internal energy U, magnetic field B and magnetic moment μ by Nu = (N - U/μB)/2, Nd = (N + U/μB)/2 (a) Use the relation T-1 = (∂S/∂U)N,B

Thermodynamics: Work done, heat transfer and internal energy

(See attached file for full problem description) 0.110 moles of a mono atomic gas follows the process shown in the figure Part A How much heat energy is transferred to or from the gas during process 1 to 2? Part B How much heat energy is transferred to or from the gas during process 2 to 3? Part C What is the tota

Tension, work done and increase in internal energy

A sledge loaded with bricks has a total mass of 18.0 kg and is pulled at constant speed by a rope. The rope is inclined at 20.0° above the horizontal, and the sledge moves a distance of 20.0 m on a horizontal surface. The coefficient of kinetic friction between the sledge and surface is 0.550. (a) What is the tension in the ro

Work and Energy - Volume, Pressure and Temperature

1. You have a 16 oz cup of coffee at 180 degrees F. That is way too hot to drink. So you want to cool the coffee off and decide to add some cold water. You add 2 ounces of cold water at 40 degrees F. How much will the water you added heat up? How much will the coffee that you poured the water into cool down? 2.

Energy absorbed per house; pressure in gas; mass

Hi, I need help with these problems; would you help me? Thank you. 1) A Carnot engine has a power output of 150 kW. The engine operates between two reservoirs at 20.0C and 500C. How much energy does it absorb per hour? 2) The internal energy in a monatomic ideal gas is 2.00 * 10^4J. The volume of the gas is 2.00 liters. Wh

Simple Ways of Expanding in thermodynamic processes

Please see attached file for full problem. Simple Ways of Expanding Part A What type of process does curve OA represent? A) adiabatic B) isobaric C) isochoric D) isothermal Part B What type of process does curve OC represent? A) adiabatic B) isobaric C) isochoric D) isothermal Part C The pressure of the s

Ideal gas equation, Internal Energy, Equipartition of energy principle

1. A scuba tank has a volume of 3500 cm³. The tank is filled with 50% (by volume) pure oxygen and 50% (by volume) pure helium. (a) How many molecules are there of each type in tank if it is filled at 20ºC to an absolute pressure of 11 atmospheres? (b) What is the ratio of the average translational kinetic energies of the t

Suraj Joshi - clarification required - wet steam properties

Suraj, Firstly, thanks for your initial answer, and apologies for not rating it. I didn't realise I needed to rate it upon receipt, rather than when convenient. If you could just clarify a couple of points relating to your answer though, we'll have another go at the rating bit. (1) "At critical point of water, T= 647.1

Laws of Thermodynamics

Question: When a gas follows path 123 on the PV diagram in the attached file, 418 J of energy flows into the system by heat, and -167 J of work is done on the gas. a) What is the change in the internal energy of the system? b) How much energy Q flows into the system if the gas follows path 143? See attached file for di

Molar heat capacity at constant volume and pressure

When 117 J of energy is supplied as heat to 2.00 moles of an ideal gas at constant pressure, the temperature rises by 2.00 K. calculate the molar heat capacity at constant pressure and the molar heat capacity at constant volume for the gas. is the gas monatomic or diatomic?