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Assignment #________
Name_______________________________________ Per. _________
Chp 8 Lecture Handout
Multiple Choice
Identify the choice that best completes the statement or answers the question.
1 Which of the following changes is chemical rather than physical?
1) Water is boiled.
2) Aluminum foil is crumpled.
3) Glass is shattered.
4) Wood is burned.
2 Each substance written to the right of the arrow in a chemical equation is a ____.
1) reactant
3) precipitate
2) product
4) catalyst
3 According to the law of conservation of mass, how does the mass of the products in a chemical reaction compare to the mass of the
reactants?
1) There is no relationship.
2) The mass of products is sometimes greater.
3) The mass of reactants is greater.
4) The masses are always equal.
4 Which of the following changes gives NO evidence that a chemical reaction has taken place?
1) A cube of solid forms a puddle of liquid.
2) A certain liquid is added to a solid, and bubbles of gas form.
3) Two liquids are mixed, and a precipitate forms.
4) Heating a blue solid turns the solid white.
5 When the following chemical reaction is balanced, what number is placed before NH 3?
N2 + 3H2  NH3
1) 1
3) 3
2) 2
4) 6
6 Which chemical equation is balanced?
1) Na + O2  Na2O
2) 2Na2 + O2  2Na2O
3)
4)
2Na + 2O2 2Na2O
4Na + O2  2Na2O
7 The ability of an apple to change color when exposed to air is a ____.
1) physical property
3) physical change
2) chemical property
4) chemical change
8 Which of the following is NOT a possible sign of a chemical change?
1) a change in state
3) the release of a gas
2) a change in color
4) the release of energy
9 When a newspaper is left in direct sunlight for a few days, the paper begins to turn yellow. The yellow color is evidence of a ____.
1) physical property
3) physical change
2) chemical property
4) chemical change
10 Which change can be reversed by changing the temperature?
1) a spoonful of pancake batter cooking in a hot pan
2) water droplets condensing on the outside of a glass of ice-cold lemonade
3) a lit firecracker exploding into bright bursts of different colors
4) a chicken egg hatching into a baby chick when the egg is kept warm
Figure 1
11 Figure 1 lists some substances and two important properties of each one. Which substance would be the best choice to use when
making a frying pan?
1) substance W
3) substance Y
2) substance X
4) substance Z
12 Which energy diagram represents an endothermic reaction?
1)
3)
2)
4)
13 How many hydrogen atoms are there in the compound
1) 3
3)
2) 8
4)
Figure 2
?
10
14
14 Refer to Figure 2. Which letter on the energy graph represents the energy of the reactants?
1) A
3) C
2) B
4) D
Figure 3
15 Figure 3 shows the Group 17 elements of the periodic table. F, Cl, Br, and I all exist as diatomic molecules. What would you
predict a molecule of At to be made of?
1) one atom of At
3) three atoms of At
2) two atoms of At
4) four atoms of At
Figure 4
16 Figure 4 shows a molecule of ammonia. Which is the correct formula for a molecule of ammonia?
1) NH
3) NH3
2) 3NH
4) N3H
Figure 5
17 Refer to Figure 5. Which word best completes the concept map?
1) energy
3) formulas
2) reactions
4) properties
Matching
Match each item with the best description below.There is only one answer for each.
1) physical change
5) product
2) conservation of mass
6) reactant
3) chemical change
7) endothermic
4) exothermic
8) subscript
18 reaction that absorbs energy _________________________________________________________________
19 frying an egg ________________________________________________________________________________
20 number of atoms in a chemical formula ______________________________________________________________
21 present before chemical reaction ______________________________________________________________________
22 reactant mass equals product mass _____________________________________________________________________
23 ice melting ______________________________________________________________________________________
24 reaction that releases energy ________________________________________________________________________
25 present after chemical reaction ______________________________________________________________________
Match the type of property with the example. Each choice will be used more than once.
1) physical property
2) chemical property
26 a box measures 4 cm by 3 cm by 8 cm _________________________________________________________________________
27 the liquid burned easily _____________________________________________________________________________________
28 the muffins baked for 20 minutes until done _____________________________________________________________________
29 the dessert tasted rich and chocolaty ___________________________________________________________________________
Match the signs of chemical change with the examples of chemical change. There is one correct answer for each.
1) the formation of a precipitate
3) release of light and heat
2) a change in color
4) the formation of a gas
30 burning wood in a fireplace __________________________________________________________________________________
31 antacid tablet in water ______________________________________________________________________________________
32 solution of sodium nitrate is mixed with a solution of lead nitrate ____________________________________________________
33 leaving peeled fruit on a kitchen counter ________________________________________________________________________
Completion
Complete each statement.
34 Photosynthesis in plants is an example of a ____________________ change.
35 The color of a material is an example of a ____________________ property.
36 The main difference between physical and chemical changes is that ____________________ changes are not reversible.
37 The evaporation of water is an example of a change in ____________________.
Figure 7
38 Refer to Figure 7. The molecule in the figure is an example of a(n) __________ molecule.
39 In an ___________ process, the reactants are more stable than the products.
Chp 8 Lecture Handout
Answer Section
MULTIPLE CHOICE
1 4
2 2
3 4
4 1
5 2
6 1
7 2
8 1
9 4
10 2
11 4
12 3
13 4
14 1
15 2
16 3
17 2
MATCHING
18 7
19 3
20 8
21 6
22 2
23 1
24 4
25 5
26 1
27 2
28 2
29 1
30 3
31 4
32 1
33 2
COMPLETION
34 chemical
35 physical
36 chemical
37 state
38 diatomic
39 endothermic