Question

first 20 elements of the periodic table

Answer 1

hydrogen
helium
lithium
beryllium
boran
carbon
nitrogen
oxygen
flourine neon sodium magnesium aluminium
silicon phosphorus sulphur chlorine argon potassium calcium
Hope it helps.

Answer 2

ydrogen-H

Helium-He

Lithium-Li

Beryllium-Be

Boron-B

Carbon-C

Nitrogen-N

Oxygen-O

Fluorine-F

Neon-Ne

Sodium-Na

Magnesium-Mg

Aluminium-Al

Silicon-Si

Phosphorus-P

Sulphur-S

Chlorine

Argon-At

Potassium-K

Calcium-Ca