Question

why hydrogen called rough elements?​

Answer 1

because he have character of IA and VIIB elements in periodic table

Answer 2

Answer:

Hey!

Hydrogen, the first element in the periodic table, is one of the most common elements found on Earth and the lightest one known to exist. An estimated 90 percent of the universe is composed of hydrogen. It can be found in nearly everything organic (that is, any material that contains the element carbon except diamond and graphite) and in all living organisms. In its pure gaseous form, hydrogen is odorless, colorless, tasteless, highly flammable, but not poisonous.

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