Atomic And Molecular Masses

Atomic mass

Atoms are very small particles and therefore their masses are also extremely small. Nowadays the method of spectroscopy is used for accurately determining the mass of an atom. But in nineteenth-century scientist used the concept of relative atomic mass for finding the mass of an atom. Elemental hydrogen was considered as the standard and its mass was assumed to be 1 (without any units).

Other elements were compared with the atomic mass of hydrogen and their relative masses were obtained. The present scenario is different and now the standard used for atomic masses is carbon 12, an isotope of carbon. This standardization has been accepted all over the globe. The mass of C-12 is 12 atomic mass units and all the elements are assigned their respective masses according to this standard. One atomic mass unit is equal to

Other elements were compared with the atomic mass of hydrogen and their relative masses were obtained. The present scenario is different and now the standard used for atomic masses is carbon 12, an isotope of carbon. This standardization has been accepted all over the globe.The mass of C-12 is 12 atomic mass units and all the elements are assigned their respective masses according to this standard. One atomic mass unit is equal to

Molecular mass

Molecular mass of an element is defined as the sum of the masses of the elements present in the molecule. Molecular mass is obtained by multiplying the atomic mass of an element with the number of atoms in the molecule and then adding the masses of all the elements in the molecule. Let us see an example: carbon dioxide.
The molecular mass of carbon dioxide