Asked Nov 10, 2019

4.00 L of ar and 2.50 L of he, each at 298 K and 1.50 atm, were mixed isothermally and isobarically. The mixture was then expanded to a final volume of 20.0 L at 298 K. Write chemical processes for each step, and determine the change in entropy for the complete process.


Expert Answer

Step 1

Calculation of number of moles :

Ideal Gas Equation:


Image Transcriptionclose

PV=nRT PV n= RT Argon: 4L 1.5atm n (0.08206L.atm/K.mol) 298K n 2.453mol Heliun 2.5L 1.5atm n (0.08206L.atm/K.mol) 298 n 0.1533mol

Step 2

Calculation of mole fraction:

Mole fraction two component system,


Image Transcriptionclose

n x= Argon 0.2453 mol 0.2453mol+0.1533 mol 0.2453mol 0.3986mol -0.6154mol 0.1533mol 0.2453mol+0.1533mol 0.1533 0.3986 0.3846mol

Step 3

Entropy of mixing o...


Image Transcriptionclose

--R{14 Inx +ng, Inx) -(8.314J/mol.K)(0.2453mol)In(0.6514)+(0.1533mol)In(0.3846)) -(8.314J/molK)(-0.2656 mol) 2.2081 J/K


Want to see the full answer?

See Solution

Check out a sample Q&A here.

Want to see this answer and more?

Solutions are written by subject experts who are available 24/7. Questions are typically answered within 1 hour.*

See Solution
*Response times may vary by subject and question.
Tagged in



Physical Chemistry

Related Chemistry Q&A

Find answers to questions asked by student like you
Show more Q&A

Q: You are in lab doing an experiment, so far this is your data: Pb(CH3COO)2 (aq) + H2S (aq) → PbS (s)...

A: In a chemical reaction; the substance which involves in conversion is said to be reactant whereas th...


Q: What are the reducing and oxidizing agents for the 3rd row?

A: Given redox reaction:


Q: What are some benefits of being able to control the rate of a chemical change?

A: The controlled rate of chemical reaction makes the process economically viable and safe. It helps in...


Q: An electron in the hydrogen atom makes a transition from an energy state of principal quantum number...

A: The relation of wavelength (λ) with the principle quantum number of the initial (ni) and the final e...


Q: What is the density of a cylinder of mass 30.00 g that was submerged in a volume of water inside a g...

A: The density of a given substance is defined as the measurement which is used to compare the amount o...


Q: Classify the possible combinations of signs for a reaction's Δ?ΔH and Δ?ΔS values by the resulting s...

A: The Gibb’s free energy change is expressed as:


Q: Which of the following gases has the weakest attractive forces between particles? A. CO2 B. He C. NO...

A: The types of attractive intermolecular forces are given below, Dipole-dipole forces,London dispersio...


Q: One cup of coffee with a mass of 216 g of coffee contains 85 mg of caffeine. What is the concentrati...

A: The mass of coffee is 216 g which contains 85 mg of caffeine. The concentration in % (m/m) can be ca...


Q: Calculate the specific heat of an unknown metal if a 32.5 g sample loses 328 J of heat when it cools...

A: Click to see the answer