Question

1 to 30 elements name with atomic number valency and atomic mass by quora

Answer 1

1. Hydrogen: Atomic number is 1

                     Valency is 1

                     Atomic Mass is 1.

2.Helium: Atomic Number is 2

                Valency is 0 (Noble gas)

                Atomic Mass is 2.

3.Lithium: Atomic Number is 3

                Valency is 1

                 Atomic Mass is 7

4.Beryllium: Atomic Number is 4.

               Valency is 2

                Atomic Mass is 9

5.Boron: Atomic Number is 5

               Valency is 3

               Atomic Mass is 11

6.Carbon: Atomic Number is 6

                 Valency is 4

                 Atomic Mass is 12.

7.Nitrogen: Atomic Number is 7

                  Valency is 3

                   Atomic Mass is 14

BONUS: From Oxygen(Z=8, A=16) to Chlorine(Z=17, A=35.5) there is a pattern for obtaining the Atomic Mass. If their Atomic Number is even, then their Atomic Mass is their double (multiplied by 2). If the Atomic Number is odd, the Atomic Mass is their double plus 1 (multiplied by 2 and added by 1) Except for Chlorine, it's Atomic Number is 17 but the Atomic Mass is 35.5 not 35.

You can also find out valency by electronic configuration (by this I mean the placement of electrons in each shells) of the element. Like for Oxygen, the configuration will be (2, 6). For the last shell to get completely filled, we need to add 2 more electrons, thus the valency is 2. For more specification, the valency is 2-, as there are more electrons than the protons, so the atom becomes an anion. By this you can figure out the rest of the valency.

These just some tricks I told you which I use, but there's no other way but to learn the Periodic Table.