Respuesta :

Explanation:

First Question

- The correct chemical formular is ;  Al2(SO4)3

Second question

The following applies;

- The mass of the products is the same as the mass of the reactants

- At least one new product formed is a gas

- Molecules are changing into different molecules

Third Question

- Zn + HCl → ZnCl2 + H2

Fourth Question

- The atoms in the original substances regroup and form a different substance

- Matter is conserved

- The same atoms are present before and after the reaction