Question

how to learn atomic masses of few elements

Answer 1

The technique to learn atomic masses

For your grade you need to remember atomic masses of first 20 elements.

The atomic mass is double the atomic number of an element. But it is not applicable for all the elements in the periodic table.

The atomic masses of elements like He, Li, C, N, O, Ne, Si, S, Cl, Ca are double the atomic number.

The atomic masses of elements like Be, B, F, Na, Mg, Al, P, Ar and K are not double the atomic number.

For these elements just double the atomic number and add 1.

Try to practice every day …..

Answer 2

approx double of atomic no.

example :- Oxygen =at.no. =8 and at. mass=16

nitrogen=at.no.=7 and at. mass=14