Solve Gas Stoichiometry: Find CH2 Molecular Formula from 2.56atm

  • Thread starter Thread starter Hollysmoke
  • Start date Start date
  • Tags Tags
    Gas Stoichiometry
Click For Summary
SUMMARY

The discussion focuses on solving a gas stoichiometry problem involving a mixture of argon gas and an unknown gas with an empirical formula of CH2. The total pressure of the gas mixture is 2.56 atm, and the user calculates the number of moles of argon as 0.00869 mol and its partial pressure as 2.49 atm. The mole fraction of argon is determined to be 0.097, leading to a conclusion that the mole fraction of the unknown gas CH2 is 0.903. The next steps involve using the ideal gas law (PV=nRT) to find the total number of moles in the vessel.

PREREQUISITES
  • Understanding of gas laws, specifically the Ideal Gas Law (PV=nRT).
  • Knowledge of mole fractions and their calculation.
  • Familiarity with empirical and molecular formulas in chemistry.
  • Basic skills in stoichiometry and gas stoichiometry calculations.
NEXT STEPS
  • Learn how to calculate molar mass from empirical formulas.
  • Study the application of the Ideal Gas Law in gas mixtures.
  • Explore the concept of partial pressures and Dalton's Law of Partial Pressures.
  • Investigate how to derive molecular formulas from empirical formulas using molar mass.
USEFUL FOR

Chemistry students, educators, and anyone involved in gas stoichiometry calculations or studying gas laws and their applications in chemical reactions.

Hollysmoke
Messages
185
Reaction score
0

Homework Statement


A sealed 1.00 L vessel contains 0.3475 g of argon gas and 6.766 g of an unknown gas at 350 K. If the total pressure of the gas mixture is 2.56 atm, and the unknown gas has an empirical formula of CH2, what is the molecular formula of the unknown gas?

Homework Equations


I get stuck about halfway. I find the mole fraction of Ar but I'm not sure if its right, if someone could help me on how to finish the problem please? How do I find the molar mass of the unknown?


The Attempt at a Solution



I used the mass of the Argon Gas to find the number of moles (0.00869 mols), then ideal gas law to find the pressure of argon gas (2.49 atm). Then using mole fractions, P1=X1*Ptot,I get X for Argon as 0.097, or 9.7% Argon Gas.

Is CH2 = 90.3% then, so X = 0.903? What do I do afterwards?
 
Physics news on Phys.org
You know the temperature, volume and pressure of the vessel. Assume that the mixture of gases acts in an ideal fashion (PV=nRT). From this you will know the total number of moles of the binary mixture. You already precisely know the number of moles of one of the components.
 

Similar threads

Chemistry Finding the molecular formula of an unknown hydrocarbon
  • · Replies 4 ·
Replies
4
Views
3K
Final Pressure of Gas Mixture After Reaction Completed
  • · Replies 10 ·
Replies
10
Views
5K
Finding Mole Fractions in a Two-Phase Equilibrium System
  • · Replies 5 ·
Replies
5
Views
3K
Solving Gas Mixture Problem: Calculate Number of Moles
  • · Replies 9 ·
Replies
9
Views
4K
Ideal Gas Law solve for partial pressure
  • · Replies 2 ·
Replies
2
Views
4K
How to Determine Mole Fraction and Mass Percent from Osmotic Pressure Data?
  • · Replies 3 ·
Replies
3
Views
2K
Question involving Gas Laws: A 6.0L flask
  • · Replies 1 ·
Replies
1
Views
4K
Chemistry Using data (Pressure vs. density) to find molecular mass .
  • · Replies 7 ·
Replies
7
Views
8K
How Much Nitrogen Gas Escapes from a Compressed Cylinder?
  • · Replies 2 ·
Replies
2
Views
3K
Chemistry Calculating Average Molecular Weight and Equilibrium Constants for Gas Mixtures
  • · Replies 33 ·
2
Replies
33
Views
19K