WorksheetsSK015 WEEK 2
Total questions: 15
Worksheet time: 17mins
Name
Class
Date
1.
For the Balanced Reaction: 3 Mg + 1 Fe2O3 → 3 MgO + 2 Fe; What is the Ratio of moles of MgO to moles Fe?
a)
3mol Mg / 2 mol Fe
b)
2 mol Mg/ 3 mol Fe
c)
1 mol Fe/ 2 mol Fe
d)
3 mol MgO / 2 mol Fe
2.
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
3.
Use the equation 2 Al + 3 Cl2 ---> 2 AlCl3. If 2 moles of aluminum and 2 moles of chlorine are reacted, identify the limiting reactant.
a)
AlCl3
b)
Cl2
c)
Al
4.
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
5.
Theoretical yield = 73g
Actual yield = 62g
Calculate the percent yield.
Actual yield = 62g
Calculate the percent yield.
a)
1.16%
b)
116%
c)
85%
d)
76%
6.
P4 + 3O2 --> P4O6
What is the limiting reactant is 12 moles of P4 react with 15 moles of O2?
What is the limiting reactant is 12 moles of P4 react with 15 moles of O2?
a)
P4
b)
O2
c)
P4O6
d)
none of the above
7.
What is a limiting reactant?
a)
the reactant that determines how much product can be made
b)
the reactant that is in excess
c)
the product that you can make the most of
d)
the amount of reactants that react with each other
8.
A reactant that remains after a chemical reaction stops
a)
stoichiometry
b)
mole ratio
c)
excess reactant
d)
limiting reactant
9.
Why is it important to identify the limiting reagent?
a)
The limiting reagent speeds up the reaction.
b)
The limiting reagent controls the amount of product formed.
c)
If there is no limiting reagent, the reaction will not occur.
d)
No stoichiometry calculations can be done without a limiting reagent.
10.
The ______________ yield is the maximum amount of product possible in a reaction. This determines the amount of product that should be produced in a perfect setting
a)
Percent
b)
actual
c)
stoichiometry
d)
theoretical
11.
If a chemist calculates the maximum amount of product that could be obtained in a chemical reaction, he or she is calculating the
a)
theoretical yield
b)
mole ratio
c)
actual yield
d)
percentage yield
12.
7. The amount of product that actually forms when a chemical reaction is carried out in a laboratory is called the _________ yield.
a)
actual
b)
theoretical
c)
percent
13.
What is the right ratio of chemicals for the BCE (Balanced Chemical Equation)?__Na + __H2O --> __NaOH + __H2
a)
2,2 --> 2,1
b)
4,4 --> 4,1
c)
1,2 --> 2,4
d)
1,2 --> 2,1
14.
What is the right ratio of chemicals for the BCE (Balanced Chemical Equation)?
__Ca + __H2O --> __Ca(OH)2 + __H2
a)
2,1 --> 2,1
b)
1,2 --> 1,1
c)
1,2 --> 2,4
d)
1,2 --> 2,1
15.
Al + HBr --> AlBr3 + H2
Balance the following equation. What is the coefficient for HBr?
Balance the following equation. What is the coefficient for HBr?
a)
2
b)
6
c)
3
d)
1
100 %
