• Science
  • Contact
  • English (UK)
  • Deutsch
  • Introduction to the Gas Laws
    • What is Pressure?
    • What is Vacuum?
    • Composition of Air
    • What is Partial Pressure?
    • Dalton's Law
    • What is Gas?
    • What is Vapour Pressure?
    • What is mean free path?
    • The mean free path for some gases at 20° C and different pressures.
    • Avogadro's Law
    • What is a Mole?
    • What is a leak rate?
    • Avogadro´s Number
    • The relative masses of molecules
    • Boyle's Law
    • Charles' Law
    • The Law of Gay-Lussac
    • The Universal Gas Law
    • The Universal Gas Constant
    • The Individual Gas Constant
    • Individual gas constants for some gases (J/kg x K)
    • The Greek Alphabet
  • The Flow of Gases in Leaks
  • Helium Leak test on Heat Exchangers
  • Leak Detection and Measuring Methods
  • Leak Detection with Tracer Gas Methods
  • Leak Test with Laser Beam
  • Literature
  • Search

^

The relative masses of molecules

  • Print

In the past these masses have been called "atomic weight or molecular weight", but this was misleading, because these numbers are only ratios between atoms or molecules.

The relative mass of molecules M (also called molar Mass) at SI-units is defined in kg/kmol. One hypothetical standard atom has the relative mass of 1/12th of the 12 C atom. The relative mass of a Helium atom is then:

M = 4 kg / kmol
or
M = 4 g / mol
 
  • Impressum