Answer:
d.
Explanation:
H2 + Cl2 = 2HCL
From the equation 2g hydrogen combine with 71g of chlorine.
So 35.5 g Cl2 combines with 1g of H2
There are 100g of Cl2 so this will, by proportion, react with 100/35.5 g hydrogen.
This is 2.8 g hydrogen so the mass of HCl formed = 102.8 g.
The amount if protons is the same as the amount of electrons, so it would be 8. The charge is -2. Look at oxygen in the periodic table.