chem homework question?

Question

okay so I have a bunch of homework questions like this, and I need to see one example done out to understand. can someone explain the process?
CaO(s) + 2HCl(aq) --> CaCl2(aq) + H2O(l)


For the reaction given above, calculate the mass of each product formed
if 12.5g of the first reactant is combined with 10.0g of the second
reactant. Indicate which substance is the limiting reactant for each case.

Answer 1

CaO(s) + 2HCl(aq) --> CaCl2(aq) + H2O(l)

Calcium Oxide combined with the mass of Hydrochloric Acid yields Calcium Chloride combined with Water.

The process is called pigmentational synthesis of (Compounds)

For the reaction given above, calculate the mass of each product formed
if 12.5g of the first reactant is combined with 10.0g of the second
reactant. Indicate which substance is the limiting reactant for each case

Heck no : ) do your own work!

Answer 2

Atomic weights: Ca = 40 O = 16 H = 1 Cl = 35.5 CaO = 56 HCl = 36.5 CaCl2 = 111 H2O = 18

12.5gCaO x 1molCaO/56gCaO = 0.223molCaO

The 12,5g CaO is given. The first factor comes from the formula weight of CaO. The grams of CaO cancel, leaving moles of CaO.

10.0gHCl x 1molHCl/36.5gHCl = 0.274mol HCl

Same reasoning as above. From the balanced equation, 0.223mol CaO would need 0.446molHCl. There is not that much HCl available. So HCl is the limiting reagent. It's a good thing that the first part of the problem gave the number of moles HCl available.

0.274molHCl x 1molCaCl2/2molHCl x 111gCaCl2/1molCaCl2 = (0.274)(111)/(2) = 15.2g CaCl2

The first factor comes from the balanced equation. The molHCl cancel, leaving molCaCl2. The second factor comes from the formula weight of CaCl2. The molCaCl2 cancel, leaving gCaCl2.

0.274molHCl x 1molH2O/2molHCl x 18gH2O/1molH2O = (0.274)(18)/(2) = 2.5gH2O