Hydrogen (H) is typically placed at the top of Group 1 on the Periodic Table. However, Group 1 consists of the allall metals and hydrogen is not a metal What reason best explains why hydrogen is placed in this group?

A Hydrogen and the other alkall metals have similar physical properties

B Hydrogen was the first element to be discovered so it is placed first on the periodic table

C Hydrogen has the same number of valence electrons as the alkall metals

D There isn't a space available to place hydrogen with the other nonmetals

Because like alkali metal hydrogen has 1 valence electron

Explanation:C

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !