Question

what is the meaning of H2is the meaning of H2 q​

Answer 1

Answer:

thanks for the free point

Answer 2

The number after the element tells how many atoms are there. H2 means two hydrogen atoms. O2 means two oxygen atoms.

The number before the element is the number of molecules. 2H2 means two molecules of hydrogen and four hydrogen atoms. 2Mg means 2 Magnesium molecules.

Some elements on their own go “alone” most metals for example: Mg, Ca….

Other elements usually not metals go in pairs H2, O2, S8.

It depends on the electrons in the last layer