3 years ago

What is first and second element of the periodic table?

2 answers:

7 0

The elements on the periodic table are listed in increasing atomic number.

Hydrogen is the first element, and has an A.N. of 1. Also, its very interesting how it doesn't need 8 valence electrons to be stable.

The second element is Helium, which has an A.N (atomic number) of two.

WINSTONCH [101]3 years ago

6 0

Hydrogen= First element,H

Helium=Second Element,He

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