J.R. S. answered • 08/31/20
Ph.D. University Professor with 10+ years Tutoring Experience
Ca(OH)2(aq) + 2HCl(aq) ==> CaCl2(aq) + 2H2O(l) ... balanced equation
When given the mass or moles of both reactants, as is the case here, we first need to find which reactant, if any, is limiting. We can do that by calculating moles or mass of product formed from each.
For Ca(OH)2: 27.6 g x 1 mol/74.09 g x 1 mol CaCl2/mol Ca(OH)2 x 110.98 g/mol = 41.3 g CaCl2
For HCl: 30.8 g HCl x 1 mol/36.5 g x 1 mol CaCl2/2 mol HCl x 110.98 g/mol = 46.8 g CaCl2
LIMITING REACTANT is Ca(OH)2
How much HCl (excess reactant) remains?
2 moles HCl reacts with 1 mol Ca(OH)2 according to the balanced equation.
27.6 g Ca(OH)2 x 1 mol/74.09 g x 2 mol HCl/mol Ca(OH)2 = 0.745 mol HCl used up
moles HCl initially present = 30.8 g x 1 mol/36.5 g = 0.844 moles
moles HCl left over = 0.844 mol - 0.745 mol = 0.0988 moles HCl left over
If you want the answer in grams it would be 0.0988 mols HCl x 36.5 g = 3.61 g left over
J.R. S.
08/31/20
Raphael Louis T.
Okay sir now I get it sorry I got confused about the answer. Thanks a lot sir I really appreciate it i dont have money to pay for tutor but because my parents are poor and i just really want to learn chemistry. thank you very much sir08/31/20
J.R. S.
08/31/20
Raphael Louis T.
sir last question08/31/20
Raphael Louis T.
According to the following reaction, how many moles of sulfur trioxide will be formed upon the complete reaction of 0.235 moles sulfur dioxide with excess oxygen gas? sulfur dioxide (g) + oxygen (g) sulfur trioxide (g)08/31/20
J.R. S.
08/31/20
Raphael Louis T.
sir what is the the maximum amount of calcium chloride that can be formed?08/31/20