WorksheetsStoichiometry, Limiting reactant and % yield formative
Total questions: 14
Worksheet time: 4hrs 30mins
Name
Class
Date
1.
2NaClO3 (s) → 2NaCl (s) + 3O2 (g)
12.00 moles of NaClO3 will produce how many grams of O2?
12.00 moles of NaClO3 will produce how many grams of O2?
a)
256 g of O2
b)
576 g of O2
c)
288 g O2
2.
Fe2O3 + 3H2 → 2Fe + 3H2O
About how many grams of H2O will be produced from 150 grams of Fe2O3?
About how many grams of H2O will be produced from 150 grams of Fe2O3?
a)
50 grams H2O
b)
60 grams H2O
c)
5000 grams H2O
d)
6000 grams H2O
3.
2Fe2O3 + C → Fe + 3CO2
You add 28 grams of carbon. You find the actual yield to be 181.2 grams of CO2. What is the percent yield of CO2? (Hint: calculate theoretical yield of CO2 first)
You add 28 grams of carbon. You find the actual yield to be 181.2 grams of CO2. What is the percent yield of CO2? (Hint: calculate theoretical yield of CO2 first)
a)
15.8%
b)
209.2%
c)
6435%
d)
15.5
4.
A student burns 1.50 mol C3H8 according to the following reaction:
C3H8 + 5O2 → 3CO2 + 4H2O
How many grams of carbon dioxide are produced?
a)
44.0 g
b)
66.1 g
c)
132 g
d)
198 g
5.
The limiting reactant
a)
slows the reaction down
b)
is used up first
c)
is the reactant that is left over
d)
controls the speed of the reaction
6.
SO2 + PCl5 --> SOCl2 + POCl3
How much SOCl2 is produced when 16.2g SO2 react with 13.7g PCl5?
How much SOCl2 is produced when 16.2g SO2 react with 13.7g PCl5?
a)
7.87g
b)
30.1g
c)
26.4g
d)
19.8g
7.
3NH4NO3 + Na3PO4 --> (NH4)3PO4 + 3 NaNO3
The reaction above allows you to make NaNO3. Assuming we start with 30 g of NH4NO3 and 50 g of Na3PO4 , identify the limiting reactant.
a)
ammonium phosphate (NH4)3PO4
b)
sodium phosphate Na3PO4
c)
ammonium nitrate NH4NO3
d)
sodium nitrate NaNO3
8.
Identify the limiting reagent when 6.00 g HCl combines with 5.00 g Mg to form MgCl2.
Mg + 2HCl --> MgCl2 + H2
a)
Mg
b)
H2
c)
MgCl2
d)
HCl
9.
CH4 + 2H2O --> CO2 + 4H2
What is the limiting reactant when 20g CH4 react with 15g H2O to produce CO2?
a)
CH4
b)
H2O
c)
CO2
d)
H2
10.
When does a chemical reaction stop?
a)
When the lab is finished
b)
When the excess reactant is used up
c)
When the limiting reactant is used up
d)
Chemical reactions never stop
11.
Fe + S --> FeS
If 7.62g Fe react with 8.67g S, what is the limiting reactant?
If 7.62g Fe react with 8.67g S, what is the limiting reactant?
a)
Fe
b)
S
c)
FeS
d)
none
12.
You need 2 pieces of bread, 1 tablespoon of peanut butter and 2 tablespoons of jelly to make a sandwich. If you have 10 pieces of bread, 4 tablespoons of peanut butter and 20 tablespoons of jelly, what is the limiting reactant?
a)
bread
b)
jelly
c)
peanut butter
d)
sandwich
13.
4NH3 + 5O2 --> 4NO + 6H2O
How many grams of NO are formed if 6.30g of ammonia react with 1.80g of oxygen?
How many grams of NO are formed if 6.30g of ammonia react with 1.80g of oxygen?
a)
0.37g
b)
0.045g
c)
1.35g
d)
11.1g
14.
P4 + 6Cl2 --> 4PCl3
The reaction of 75.0g P4 with excess chlorine gas produces 110g PCl3 in lab. Find the theoretical yield and calculate percent yield for the reaction.
The reaction of 75.0g P4 with excess chlorine gas produces 110g PCl3 in lab. Find the theoretical yield and calculate percent yield for the reaction.
a)
78%
b)
64%
c)
27%
d)
33%
100 %
