11. I would say physical because the color of the item is changed and the texture and density is changed aswell.
I have provided the steps to figure out the number of atoms in the chemical compound.
The balanced chemical reaction is:
2HCl + Ca = CaCl2 + H2
We are given the amount of the reactants to be used for the reaction. These values will be the starting point of our calculations.
100 g HCl ( 1 mol HCl / 36.46 g HCl ) = 2.74 mol HCl
100 g Ca ( 1 mol Ca / 40.08 g ) = 2.08 mol Ca
From the reaction, the mole ratio of the reactants is 2:1 where every 2 moles of hydrochloric acid, 1 mole of calcium is required. Therefore, the limiting reactant for this case is calcium.
