explanation of what 'relative atomic mass' and relative molecular mass.

Question

anonymous · Answer

can you explain this in detail in a paragraph or more

chmvijay · Answer

o consider the masses of atoms measured in grams, for example, would be to deal inconveniently with extremely small numbers. Rather, the mass of an atom is compared with that of an atom of carbon-12. The relative atomic mass of carbon-12 is taken to be 12. Relative masses have no units because they have cancelled in their calculation.
Some elements have isotopes. In calculating the relative atomic mass of an element with isotopes, the relative mass and proportion of each is taken into account. For example, naturally occurring chlorine consists of atoms of relative isotopic masses 35 (75%) and 37 (25%). Its relative atomic mass is 35.5. 
Ar = (75/100 x 35) + (25/100 x 37) = 35.5

anonymous · Answer

chmvijay can you also help me find some in organic and organic dot and cross diagrams as well as a salt. thanks
is there any website that has these information or not.