primary reactant.primary product.9. To determine the limiting reactant in a chemical reaction, one must know theavailable amount of one of the reactants.amount of product formed.......
111 g
188 g
451 g
8. A chemical reaction involving substances A and B stops when B is completely used. B is the
excess reactant.
limiting reactant.
primary reactant.
primary product.
9. To determine the limiting reactant in a chemical reaction, one must know the
available amount of one of the reactants.
amount of product formed.
available amount of each reactant.
speed of the reaction.
10. Consider the following reaction:
Mg2Si + 2H2O → 2Mg(OH)2 + SiH4
Calculate the number of grams of silane gas, SiH4, formed when 90.4 g of Mg2Si react with excess H2O.
75.7 g SiH4
25.4 g SiH4
37.9 g SiH4
49.2 g SiH4
1. 0.88 mol
2. stoichiometry
3. b
4. 3.0 mol
5. 7 mol
6. 4 mol * molecular weight of SO3
7.
8. maybe c
9. a
10. 2*(90.4/molecular weight of SiH4)
im not gonna tell you the answers to all of them because you need to do your own homework. you will learn better that way. however i will give you an explanation as to how you should approach each problem.
1. the question suggests that the reactants have completely reacted. so you can use the mole ratio. look at the coefficients. if 4 moles of iron react, then 2 moles of iron oxide is produced.
so for every mol of iron reacted you get half that amount of iron oxide (4/2). so divide the amount of mol of Fe by that constant and there is your answer. an easy way to remember what to multiply by is... well ill give you an example:
if i have X mols of oxygen and i want to know how many mols of iron that corresponds to. i say:
X mol O2 * (4 mol Fe) / (3 mol O2)
notice how the mol of oxygen cancels because it is in both the numerator and denominator and all you are left with is mol Fe and my answer will be (4X/3) mols of Fe. you can use that thought process to help deciding what you need to multiply and divide by
