If Chelcy and Allyson reacted 2.55 grams of Mg with excess hydrochloric acid (HCl), how many grams of MgCl2 will they theoretically produce? Mg(s) + HCl (aq) → H2 (g) + MgCl2 (aq)

Question

?g MgCl2

Answer 1

Mg + 2HCl ==> MgCl2 + H2
mols Mg = grams/atomic mass.
Using the coefficients in the balanced equation, convert mols Mg to mols mgCl2 (looks like 1:1 to me).
Now convert mols MgCl2 to grams. g = mols x molar mass.

Answer 2

18.5