Calculating Mass of Helium Gas at STP

  • Thread starter kasse
  • Start date
  • Tags
    Gas Mass
In summary, to calculate the mass of helium gas at STP, you can use the ideal gas law and the molar mass of helium. The ideal gas constant (R) is a proportionality constant that relates the properties of a gas to its temperature, pressure, and volume. The molar mass of helium is 4.003 g/mol and the standard temperature and pressure (STP) for gases is a temperature of 273.15 K and a pressure of 1 atm. It is important to calculate the mass of helium gas at STP for various reasons, including determining the amount of helium present, understanding gas behavior, and designing gas storage and transport systems.
  • #1
kasse
384
1
[SOLVED] Mass of gas

Homework Statement



What mass of He gas occupies 8.5 L at 273 K and 1 atm?

Homework Equations



PV = nRT

The Attempt at a Solution



n = PV/RT = (101 kPa * 8.5 L)/(8.3145 * 273 K) = 2.64E-3 mol --> 10.6 g

My solutions manual says 1.52 g. Am I right or wrong?
 
Physics news on Phys.org
  • #2
2.64E-3 mole? Really? I seem to remember a mole of gas at STP is 22.4 liters. What does a mole of helium mass? The book is right.
 

1. How do you calculate the mass of helium gas at STP?

To calculate the mass of helium gas at STP (standard temperature and pressure), you can use the ideal gas law: PV = nRT. This equation relates the pressure (P), volume (V), number of moles (n), gas constant (R), and temperature (T) of a gas. By rearranging the equation to solve for n, you can then use the molar mass of helium (4.003 g/mol) to calculate the mass in grams.

2. What is the value of the ideal gas constant (R) in the ideal gas law?

The ideal gas constant (R) is a proportionality constant that relates the properties of a gas to its temperature, pressure, and volume. The value of R depends on the units used for pressure, volume, and temperature. In SI units, the value of R is approximately 8.314 J/mol·K.

3. What is the molar mass of helium?

The molar mass of helium is 4.003 g/mol. This value is calculated by taking the atomic mass of helium (4.003 amu) and converting it to grams per mole using Avogadro's number (6.022 x 10^23).

4. What is the standard temperature and pressure (STP) for gases?

The standard temperature and pressure (STP) for gases is a set of conditions used for comparison of gas properties. It is defined as a temperature of 273.15 K (0 °C or 32 °F) and a pressure of 1 atmosphere (atm) or 101.325 kilopascals (kPa).

5. Why is it important to calculate the mass of helium gas at STP?

Calculating the mass of helium gas at STP is important for various reasons. It can help scientists determine the amount of helium present in a given volume, which is important for industries that use helium for various applications. It can also be used to determine the efficiency of gas reactions and to understand gas behavior under certain conditions. Additionally, calculating the mass of a gas at STP can help with the design and operation of gas storage and transport systems.

Similar threads

Engineering Calculating the mass of air in a pressurised air tank
    • Engineering and Comp Sci Homework Help
Replies
14
Views
1K
Root Mean Square Speed Units Question
    • Advanced Physics Homework Help
Replies
4
Views
10K
Predicting Remaining Pressure in Compressed Gas Cylinder
    • Mechanical Engineering
Replies
3
Views
933
How to find the Density of Air with PV=nRT?
    • Biology and Chemistry Homework Help
Replies
7
Views
2K
Chemistry Calculating Kp of o2 and o3 equilibrium
    • Biology and Chemistry Homework Help
Replies
3
Views
3K
Calculating Hydrogen Mass from Ideal Gas Law
    • Introductory Physics Homework Help
Replies
3
Views
3K
Ideal Gas Law and Pressure at 80°C
    • Introductory Physics Homework Help
Replies
2
Views
2K
Find the amount of ethanol (70 degC) in gas phase in a tank at atm
    • Engineering and Comp Sci Homework Help
Replies
3
Views
989
Calculating Moles and Molecules of Oxygen in a Gas Cylinder
    • Advanced Physics Homework Help
Replies
10
Views
2K
Thermodynamics -- piston-cylinder device with helium is compressed....
    • Engineering and Comp Sci Homework Help
Replies
1
Views
2K

Hot Threads

Recent Insights

Back
Top