Question

why hydrogen is the lightest element.

Answer 1

Because it is made up of helium atoms and has first place in periodic table

Answer 2

DEAR STUDENT

HYDROGEN is the lightest element because it has only one proton in the nucleus and one electron in its outer shell.......

ADDITIONAL INFORMATION

HYDROGEN is the most abundant element in the universe........its atomic number is 1 and atomic mass is 1.00794........

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