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UNit 6- Chemical Reactions, Balancing Eqns, Stoichiometry

Total questions: 73

Worksheet time: 6hrs 5mins

Name
Class
Date
1.
Using the following equation:
Fe2O3(s) + 3H2(g) → 2Fe(s) + 3H2O(l)
How many moles of iron can be made from  6 moles H2
a)
4 moles Fe
b)
6 moles Fe
c)
9 moles Fe
d)
2 moles Fe
2.
2 NaClO3 (s) --> 2NaCl (s) +3 O2 (g)  
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
3.
B2H6 + 3O2 -->2 HBO2 + 2 H2O
 What mass of O2 will be needed to burn 36.1 g of B2H6?
a)
13.8 g O2
b)
3.86 mol of O2
c)
124 g O2
4.
4 Al + 3 O2 –> 2 Al2O How much aluminum would be needed to completely react with 45 grams of O2?
a)
1.05 moles
b)
3.75 moles
c)
1.875 grams
d)
1.875 moles
5.
Balance the following reaction :
 
CaC₂(s)   +   H₂O(l)   -->   C₂H₂(g)   +   Ca(OH)₂(aq)
a)
1,2,2,2
b)
1,2,1,1
c)
2,1,1,1
d)
2,1,2,1
6.
 CaC₂(s) + 2H₂O(l)   -->   C₂H₂(g)   + Ca(OH)₂(aq)
how many grams of Ca(OH)₂ would be formed with 3.20 moles of CaC₂?
a)
119 g
b)
21.2 g
c)
114 g
d)
237 g
7.
Using the following equation:
4NH3(g) + 5O2(g) --> 4NO(g) + 6H2O(l)
How many grams of oxygen gas are needed to react with 56.8 grams of ammonia?
a)
45.08 g O2
b)
133.33 g O2
c)
260.77 g O2
d)
75.92 g O2
8.
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
9.
2 CO (g) + O2(g) → 2 CO2 (g)
In the formation of CO2 from CO and oxygen, how many Liters of CO2 are produced by the reaction of 8 mols of O2 with an excess of carbon monoxide?
a)
0.178 L
b)
358.4 Liters
c)
704 grams
d)
0.36 grams
10.
 SiO2 + 3C → SiC + 2CO
I need to add 8 moles of Carbon to the reaction. How many grams of Carbon should I weigh?
a)
96 g
b)
0.67 g
c)
2.67 g
d)
48 g
11.
Cl2 + 2 KBr → Br2 + 2 KCl
How many grams of potassium chloride can be produced from 356 g of chlorine and 356 g of potassium bromide?
a)
749 g
b)
223 g
c)
479 g
d)
814 g
12.
A chemist interested in the efficiency of a chemical reaction would calculate the
a)
mole ratio
b)
rate of reaction
c)
percent yield
d)
energy released
13.
Fe (s) + S (l) --> FeS (s)  

In the experiment above, 7.62 g of Fe are allowed to react with 8.67 g of S.
How much FeS is formed?
a)
14.8 g
b)
12.2 g
c)
13.7 g
d)
19.9 g
14.
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
15.
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
16.

Balance this equation

_Al +_HCl --> _H2 +_AlCl3

a)

2,6,3,2

b)

it's already balanced

c)

4,12,3,4

d)

2,1,4,5

17.
Which problem is balanced?
a)
PbO2 + 2H2--> H2SO4
b)
SO2 + H20 --> H2SO4
c)
2Na + 2H2O --> 2NaOH + H2
d)
2Na + 2H2O --> 2NaOH + H
18.
Number of H in 3(NH₄)₂CrO₄
a)
4
b)
6
c)
8
d)
24
19.
What is the left part of a chemical equation called?
2H2 + O2 --> 2H2O
a)
Reactants
b)
Products 
c)
Yields 
d)
Chemical Equation 
20.
Which of the following shows the correct way to balance the chemical equation?
Fe + O2 -> Fe2O3
a)
4Fe + 3O2 -> 2Fe2O3
b)
2 Fe + 3O2 -> Fe2O6
c)
4 Fe + O6 -> 2Fe2O3
d)
None of the options are correctly balanced.
21.
Which of the following reactions is balanced?
a)
2CH4 + O2 -> CO2 + H2O
b)
CH4 + 2O2 -> CO2 + H2O
c)
CH4 + 2O2 -> CO2 + 2H2O
d)
None of the chemical equations are balanced.
22.
Which coefficients balance this equation:
NH3  +  O2 ---->   NO  + H2O
a)
2,3,5,6
b)
5,5,4,6
c)
4,6,4,5
d)
4,5,4,6
23.
Is the following equation balanced or unbalanced?
Fe + S --> FeS
a)
balanced
b)
unbalanced
24.

In the equation shown, what are the product(s)?

a)

N2 + H2

b)

NH3

25.

Is this equation balanced?

a)

Yes, everything appears the same amount on each side.

b)

No, there are too many hydrogen on the left side.

c)

No, there are too many oxygen on the left side.

26.

Is this equation balanced?

a)

Yes, everything appears the same amount on each side.

b)

No, there are too many hydrogen on the left side.

c)

No, there are too many oxygen on the left side.

27.
Which is the correct formula for:
 three hydrogen (H)
one sulfur (S)
four oxygen (O)
a)
H3SO4
b)
HSO4
c)
H4S3O
d)
H2O
28.

Which type of reaction has only one reactant?

a)

synthesis

b)

Double replacement

c)

Chemical reaction

d)

decomposition

29.

4Si + S8 --> 2Si2S4


What type of reaction is this?

a)

Synthesis

b)

Decomposition

c)

Single displacement

d)

Double displacement

30.
AB + CD = AD + CB
a)
Double Replacement
b)
Single Replacement
c)
Combustion
d)
Decomposition
31.
A + BC = B + AC
a)
Single Replacement
b)
Combustion
c)
Double Replacement
d)
Synthesis
32.
Fe + H2SO4 --> Fe2(SO4)3 + H2
a)
Synthesis (combination)
b)
Decomposition
c)
Single replacement
d)
Combustion
33.
What type of reaction occurs between an element and a compound?
Zn + 2HCl --> ZnCl2 + H2
a)
Synthesis
b)
Decomposition
c)
Single Replacement
d)
Double Replacement
34.
A chemical reaction in which a compound or element burns by reacting with oxygen is called a(n)
a)
combination reaction
b)
decomposition reaction
c)
combustion reaction
d)
carbonate decomposition reaction
35.
The reaction below is an example of?
AgNO3 + NaCl 
→ AgCl + NaNO3
a)
Single Replacement
b)
Double Replacement
c)
Decomposition
d)
Combustion
36.
What type of reaction is illustrated below?
2HI --> H2  +  I2
a)
synthesis
b)
decomposition
c)
single replacement
d)
double replacement
37.

Which of the following reactions involves the ions of two compounds exchanging places to form two new compounds?

a)

Synthesis

b)

Double replacement

c)

Combustion

d)

Single Displacement

38.

Balance this equation.

_CF4 + _Br2 -- _CBr4 + _F2

a)

2,1,2,1

b)

1,2,2,1

c)

1,2,1,2

d)

2,2,2,2

39.
What type of reaction is C3H8 + 5O2 => 3CO2 + 4H2O?
a)
combination
b)
decomposition
c)
combustion
d)
both combination and decomposition
40.

Fill in the blank. (Copper has a charge of 2+)

Cu+ AgNO3 → Ag + _____

a)

Cu(NO3)2

b)

CuNO3

c)

CuAg

d)

Cu

41.

What type of reaction is this?

2 C6H14 + 19 O2 → 12 CO2 + 14 H2O

a)

Single Replacement

b)

Double Replacement

c)

Combustion

d)

Decomposition

42.

Predict the products for the this Single Replacement reaction:

K + HCl →

a)

KCl + H2

b)

KHCl

c)

KH + Cl2

d)

HCl + K2

43.

Predict the products for the this Double Replacement reaction:

AgNO3 + KCl →

a)

AgCl + KNO3

b)

AgK + ClNO3

c)

KAg + NO3Cl

d)

AgCl + 3 KNO

44.

Predict the product of this synthesis reaction:

Al + S₈ →

a)

AlS

b)

AlS8

c)

Al2S

d)

Al2S3

45.

Name the ionic compound SnSe2

a)

Tin diselenide

b)

Tin (IV) Selenide

c)

Tin selenide

d)

Tin (II) triselenide

46.

Name the following ionic compound: Cs2S

a)

cesium sulfide

b)

cesium sulfate

c)

cesium II sulfate

d)

cesium II sulfide

47.
The covalent compound N2O5 would be named
a)
nitrogen oxide.
b)
dinitrogen oxide.
c)
nitrogen pentoxide.
d)
dinitrogen pentoxide.
48.

What are the products of ALL combustion reactions?

a)

Carbon Dioxide and Water

b)

Smoke and Ash

c)

Fire and Carbon Dioxide

d)

Water and Ash

49.

What does the symbol (aq) stand for?

a)

Aquatic

b)

Aqueous

c)

Aqua

d)

Aquarium

50.

Use the activity series, seen in the image, to determine if the reaction will occur.

Ca + Fe2S3 --> ?

a)

Yes, the reaction will occur

b)

No, the reaction will not occur

c)

Cannot be determined

51.

Which coefficient should be placed in front of NH3 to balance this equation?


NH3 + H2SO4 --> (NH4)2SO4

a)

1

b)

2

c)

3

d)

1,000,000,000

52.

Which coefficient should be placed in front of Lithium to balance this equation?


AlCl3 + Li --> LiCl + Al

a)

1

b)

2

c)

3

d)

0.00000000000001

53.

Which coefficient should be placed in front of O2 to balance this equation?


C2H6 + O2 --> H2O + CO2

a)

3.5

b)

7

c)

9

d)

14

54.

What type of reaction is this?


Pb(NO3)2 + 2KI --> 2KNO3 + PbI2

a)

Double Replacement

b)

Single Replacement

c)

Synthesis

d)

Decomposition

55.

Which law states that Matter cannot be created or destroyed?

a)

Law of Conservation of Matter

b)

Law of Gravity

c)

Law of Equivalent Exchange

d)

Law of Matter ad Infinitum

56.

Fun Fact: What do you call the original, unbalanced equation you have to start with?

a)

Equation Skeleton

b)

Balanced Equation

c)

Free Response Question

d)

DBQ

57.

Which of the following could be an indication that a chemical reaction has occurred?

SELECT ALL THAT APPLY!!!

a)

Bubbles

b)

Precipitate Formation

c)

Change in Mass

d)

Change in Shape

e)

Change in Temperature

58.
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
59.
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
60.

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

61.

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

62.
What is the limiting reactant if 10 moles of NH3  react  with 30.0 moles of NO?
4NH3+6NO --> 5N2 + 6H2O
a)
NH3
b)
NO
c)
N2
d)
water
63.

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.

64.
2. True or False?
A chemical reaction stops before the limiting reagent is used up.
a)
True
b)
False
65.
1 Body + 4 Tires --> 1 car
How many cars can you make with 92 tires and 34 bodies? 
a)
23
b)
34
c)
68
d)
46
66.
1 Body + 4 Tires --> 1 car
How many cars can you make with 92 tires and 34 bodies? 
In this senario the tires would be the _____________  reactant. 
a)
Limiting 
b)
Excess 
67.
CH4  +  2O2  →  CO2  +  2H2O
24 grams of CH4 was added to the above reaction. Calculate the theoretical yield of CO2.
a)
66 grams
b)
132 grams
c)
33 grams
d)
8.72
68.
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
69.

When reacting Na with Cl2, we calculated that the theoretical yield should be 13 grams. Our actual yield was 12.5 grams. What is the percent yield?

a)

90.4%

b)

104%

c)

96.15%

d)

1.04%

70.

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)

a)

58.83%

b)

308%

c)

6435%

d)

15.5

71.
Theoretical yield = 73g
Actual yield = 62g
Calculate the percent yield.
a)
1.16%
b)
116%
c)
85%
d)
76%
72.

11.

LiOH + KCl → LiCl + KOH


b) I actually produced 6 grams of lithium chloride and I began this reaction with 20.0 grams of lithium hydroxide. What is my percent yield?

a)

16.9%

b)

5.91%

c)

1.88%

d)

12.3%

73.
In a lab, a scientist calculate he should produce 12.3 grams of product in his experiment. When he is finished collecting his product it weighs 10.1 grams. What is his percent yield?
a)
82%
b)
0.82%
c)
10.1 %
d)
100%