Name: 
 

10.1 Quiz


Modified True/False
Indicate whether the statement is true or false.  If false, change the identified word or phrase to make the statement true.
 

 1. 
The products are the substances formed as the result of a chemical reaction. _________________________

 

 2. 
Melting ice is an example of a chemical change. ______________________________

 

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 

 3. 
When a chemical change occurs:
a.
atoms are rearranged.
b.
the law of conservation of mass is always obeyed.
c.
the chemical properties of new substances are different from the ones you started with.
d.
All of the above
 

 4. 
Your teacher mixes a liquid and a solid in a beaker. Which of the following is NOT evidence that a chemical change has occurred?
a.
A drop of liquid that spills on the lab table quickly evaporates.
b.
The temperature of the mixture changes from 20°C to 10°C.
c.
Bubbles form in the beaker.
d.
The mixture changes color.
 

 5. 
The principle of conservation of mass is satisfied in a chemical equation when:
a.
the same kinds of atoms appear in the reactants and products.
b.
the same number of each type of atom appears on the equation’s reaction side and product side.
c.
the sum of the coefficients on the reactant side is the same as the sum of the coefficients on the product side.
d.
each atom on the product side has the same subscript that it had on the reactant side.
 
 
Answer the following questions about the chemical reaction for the formation of rust:
Fe + O2 nar002-1-101.jpg Fe2O3
 

 6. 
Identify the reactant(s):
a.
Fe and Fe2O3
b.
Fe and O2
c.
Fe2O3
d.
O2 and Fe2O3
 

 7. 
Identify the product(s):
a.
Fe and Fe2O3
b.
Fe and O2
c.
Fe2O3
d.
O2 and Fe2O3
 

 8. 
Is the chemical reaction for the formation of rust balanced? If not, select the correct equation from the ones listed below.
a.
Yes, it is balanced.
b.
No, this is balanced: 2Fe + O2 mc008-1-101.jpg Fe2O3
c.
No, this is balanced: 4Fe + 3O2 mc008-2.jpg 2Fe2O3
d.
No, this is balanced: 3Fe + 2O2 mc008-3.jpg 3Fe2O3
 
 
Answer the following questions about the chemical reaction for the combustion of methane gas:
CH4 + O2 nar003-1-101.jpg CO2 + H2O
 

 9. 
Identify the reactants.
a.
CO2 and H2O
b.
CH4 and O2
c.
O2 and H2O
d.
CH4 and CO2
 

 10. 
Identify the products.
a.
CO2 and H2O
b.
CH4 and O2
c.
O2 and H2O
d.
CH4 and CO2
 

 11. 
Is the chemical reaction for the combustion of methane balanced? If not, select the correct equation from the ones listed below.
a.
Yes, it is balanced.
b.
No, this is balanced: CH4 + O2 mc011-1.jpg CO2 + 4H2O
c.
No, this is balanced: CH4 + 2O2 mc011-2.jpg CO2 + 2H2O
d.
No, this is balanced: CH4 + 4O2 mc011-3.jpg CO2 + H2O
 

 12. 
Balance the following equation to demonstrate the conservation of atoms in a reaction. Choose the answer that provides the correct coefficients for each reactant and product:
____ Al2O3 mc012-1.jpg ____ Al+ ____ O2
a.
(2, 4, 3)
b.
(4, 3, 2)
c.
(3, 2, 4)
d.
(2, 3, 4)
 

 13. 
A reaction is exothermic if forming the new bonds:
a.
requires more energy than it took to break the old bonds.
b.
takes the same amount of energy as was needed to break the old bonds.
c.
absorbs energy from the system, causing a temperature drop.
d.
releases more energy than it took to break the old bonds.
 

 14. 
In which of the following situations does water undergo a change in physical properties?
a.
The bathroom fills with steam when you take a hot shower.
b.
You pour a glass of water from the faucet.
c.
Water is broken down to yield H2 and O2.
d.
When hydrogen is used as a fuel for rockets, water is a product.
 

 15. 
Balance the following equation to demonstrate the conservation of atoms in a reaction. Choose the answer which provides the correct coefficients for each reactant and product.
____ CS2 + ____ O2 mc015-1-101.jpg ____ CO2 + ____ SO2
a.
(1, 3, 1, 2)
b.
(1, 2, 1, 1)
c.
(1, 6, 1, 2)
d.
(2, 6, 2, 2)
 

 16. 
If you designed your own experiment to prove the law of conservation of mass, what conditions would be required?
a.
You must find the mass of the reactants before the reaction and find the mass of the products after the reaction.
b.
You must find the mass of the reactants before the reaction, find the mass of the products after the reaction, AND perform the reaction in a closed system.
c.
You must choose a combustion reaction.
d.
You must use baking soda and vinegar because the law applies only to these substances.
 

Completion
Complete each statement.
 
 
Select the correct term to complete each sentence. There are extra terms in the list.

14167
exothermicbalancedendothermic
activation energyreactionchemical
 

 17. 
A(n) ____________________ equation for a chemical reaction correctly preserves the number and type of atoms on both sides of the reaction.
 

 

 18. 
The chemical formula 2C3H7OH means you have 6 atoms of carbon, ____________________ atoms of hydrogen, and 2 atoms of oxygen.
 

 

Short Answer
 

 19. 
For the following antacid reaction, list the reactants and the products:
2HCl + CaCO3 ® CaCl2 + CO2 + H2O
 

 20. 
Your teacher mixes two clear liquids in a beaker. Name three changes in the mixture that would provide evidence that a chemical reaction had occurred.
 

Problem
 

 21. 
Balance the following chemical equation:

Al + O2 ® Al2O3
 

 22. 
Balance the following chemical equation:

HgO ® Hg + O2
 

 23. 
Balance the following equation:

K + H2O ® KOH + H2
 

 24. 
Write the balanced equation for the following reaction:
The fuel used in gas grills is called propane (C3H8). Propane reacts with oxygen gas (O2) found in the air to produce carbon dioxide gas (CO2) and water vapor (H2O).
 

Essay
 

 25. 
When you mix baking soda and vinegar, the mixture bubbles violently and the temperature drops. Is this a chemical change or a physical change? Provide evidence to support your answer.
 

 26. 
Explain the statement, “Chemical reactions conserve mass.”
 

 27. 
When balancing chemical equations, why can’t you change the subscripts of the molecules?
 



 
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