6.0m(mol/kg) of HCl
125mL H2O = 0.125kg
6mol/kg = n mol/0.125kg, n = 0.75mol
When 0.75mol of HCl reacts, 0.75/2=0.375mol of H2 is produced. H2 = 2g/mol
So, 0.375mol H2 = 0.75g
Answer:
CaS
Explanation:
calcium is Ca2+ and sulfur is S2- because the charges are equal you only need one of each atom, so the answer is CaS