URGENT! Could someone please answer the questions below? I need the steps not just the answer. THANKS!?

For each of the following unbalanced equations, calculate how many moles of the second reactant would be required to react completely with exactly 25.0 g of the first reactant. Indicate clearly the mole ratio used for each conversion. A.Mg(s)+CuCl2(aq)-MgCl2(aq)+Cu(s)...i know this equation is... show more For each of the following unbalanced equations, calculate how many moles of the second reactant would be required to react completely with exactly 25.0 g of the first reactant. Indicate clearly the mole ratio used for each conversion.
A.Mg(s)+CuCl2(aq)-MgCl2(aq)+Cu(s)...i know this equation is 25(1/24.31)(1/1)=1.03...but dont know how where the 24.31 came from?
B.AgNO3(aq)+NiCl2(aq)-AgCl(s)+Ni(NO3)2....
C.NaHSO3(aq)+NaOH(aq)-Na2SO3(aq)+H20(l....
D.KHCO3(aq)+HCl(aq)-KCl(aq)+H20(l)+CO2....
2 answers 2