LR whiteboard practice
NH3 + O2  NO + H2O.
In an experiment, 3.25 g of NH3 are allowed to
react with 3.50 g of O2.
a. Which reactant is the limiting reagent?
b. How many grams of NO are formed?
NH4NO3 + Na3PO4  (NH4)3PO4 + NaNO3
Which reactant is limiting, assuming we
started with 30.0 grams of ammonium nitrate
and 50.0 grams of sodium phosphate. What
is the mass of NaNO3 that can be formed?
C4H9OH + NaBr + H2SO4 C4H9Br + NaHSO4 + H2O
If 15.0 g of C4H9OH react with 22.4 g of NaBr to
yield 17.1 g of C4H9Br, what is the percent yield
of this reaction?
CaCO3 + FePO4  Ca3(PO4)2 + Fe2(CO3)3
Which reactant is limiting, assuming we start
with 100. grams of calcium carbonate and
45.0 grams of iron (III) phosphate. What is
the mass of iron carbonate that can be
formed?
100.g CaCO3 
1 mol CaCO3 1 mol Fe2(CO3)3 291.7 g Fe2(CO3)3


 97.2 g
100 g CaCO3
3 mol CaCO3
1 mol Fe2(CO3)3
1 mol FePO4 1 mol Fe2(CO3)3 291.7 g Fe2(CO3)3
45.g FePO4 


 43.5 g
150.85 g FePO4
2 mol FePO4
1 mol Fe2(CO3)3
CuCl2 + NaNO3  Cu(NO3)2 + NaCl
a) If 15 grams of copper (II) chloride react
with 20. grams of sodium nitrate, how
much sodium chloride can be formed?
b) What is the name of the limiting reagent?
__________________
c) If 11.3 grams of sodium chloride are
formed in the reaction, what is the percent
yield of this reaction?
C2H6 + O2  CO2 + H2O
a) If 16.4 g of C2H6 reacts with 0.980 mol of
O2 how many grams of carbon dioxide
gas will be produced?
Fe (s) + S (l)  FeS (s)
In one experiment, 7.62 g of Fe are allowed to
react with 8.67 g of S.
What is the limiting reagent, and what is the
reactant in excess?
Calculate the mass of FeS formed.
4 C3H6 + 6 NO → 4 C3H3N + 6 H2O + N2
What mass of C3H3N can be made when 21.6 g
of C3H6 react with 21.6 g of NO?
Calculate the percent yield for the reaction:
P4 (s) + 6 Cl2 (g) → 4 PCl3 (l)
if 75.0 g of phosphorus reacts with excess
chlorine gas to produce 111.0 g of phosphorus
trichloride.
MnO2 + 4 HCl → MnCl2 + Cl2 + 2 H2O
If 0.45 mols of MnO2 react with 48.2 g of HCl,
how many grams of Cl2 could be produced?
Calculate the percent yield for an experiment in
which 5.50 g of SOCl2 was obtained in a reaction
of 5.80 g of SO2 with excess PCl5. Use the
following equation:
SO2 (l) + PCl5 (l) → SOCl2 (l) + POCl3 (l).
Cl2 (g) + SiO2 (s) + C (s) → SiCl4 (l) + CO (g)
How much CO gas can be produced from 15.0 g
of SiO2?
Ans: 14.0 g CO
Fe(OH)2 + H3PO4 → Fe3(PO4)2 + H2O
a. If 3.20 g of Fe(OH)2 is treated with 2.50 g of
phosphoric acid, what is the limiting reagent
and what is the reactant in excess?
b. How many grams of Fe3(PO4)2 precipitate can
be formed?
c.
If 3.99 g of Fe3(PO4)2 is actually obtained,
what is the percent yield?
CO (g) + 2 H2 (g) → CH3OH (l)
Suppose 356g of CO is mixed with 65.0g of H2.
Which is the limiting reactant? What is the
maximum mass of methanol that can be
formed?
ANS: CO is limiting, 408 g CH3OH formed
SiCl4 (l) + 2 Mg (s) → Si (s) + 2 MgCl2 (s)
Suppose that 225g SiCl4 is mixed with 225g of
Mg. Is one of these reactants in short supply? If
so, how much silicon can be formed if the
reaction goes to completion?
ANS: SiCl4 is limiting, 37.2 g Si formed
You have 20.0g of elemental sulfur, S8, and 160g
of O2. Which is the limiting reactant? What mass
of SO2, in grams, is formed in the complete
reaction if the formula for the reaction is…
S8 (s) + 8 O2 (g) → 8SO2 (g)
ANS: S8 is limiting, 40.0 g SO2 formed
TiO2 (s) + 2 Cl2 (g) + C (s) → TiCl4 (l) + CO2 (g)
If one begins with 125g each of Cl2 and C, but
plenty of TiO2-containing ore, which is the
limiting reactant in this reaction? What quantity
of TiCl4, in grams, can be produced?
ANS: Cl2 is limiting, 167 g TiCl4 produced
Cl2(g) + NaI(aq) → NaCl(aq) + I2(s)
Suppose that a solution containing 25.0 g NaI
reacts with 5.00 g of Cl2. What mass of iodine
will be produced from the reaction above?