Question

name 20 metals having atomic mass less than 50

Answer 1

The first twenty elements of the periodic table all have atomic mass <50. They are: Hydrogen, Helium, Lithium, Beryllium, Boron, Carbon, Nitrogen, Oxygen, Flourine, Neon, Sodium, Magnesium, Alluminium, Silicon, Phosphorus, Sulphur, Chlorine, Argon, Potassium, Calcium.

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