Deck 8: Chemical Reactions

Question 1

Consider the following particulate-level representation.The larger spheres represent N and the smaller spheres represent H. Which of the following correctly characterizes this representation?

A)The reactant could be represented as NH₃.
B)The products of the reaction are N₂ and H₂.
C)The equation is "balanced".
D)If the equation for the reaction were written as shown above the coefficient of the nitrogen containing product would be 4.
E)All of these correctly characterize this reaction.

Answer 1

All of these correctly characterize this reaction.

Question 2

Balance the equation C₈H_18(l)+ ___ O₂(g)→ ___ CO₂(g)+ ___ H₂O_(l).
What is the coefficient for O₂(g)?

A)16
B)9
C)25
D)12
E)50

Answer 2

25

Question 3

Which of the following generally indicates the possibility of a chemical change?
i.Color change
ii.Formation of a solid
iii.Formation of a gas
iv.Absorption or release of heat energy
v.Emission of light energy

A)All
B)All but i
C)All but ii
D)All but iii
E)All but v

Answer 3

All

Question 4

Calcium combines with bromine to make calcium bromide.Write the balanced chemical equation for this reaction.What is the coefficient for bromine?

A)1
B)2
C)3
D)4
E)5

Question 5

What is the coefficient for H₂ when the equation ___ Ba + ___ H₃AsO₄ → ___ H₂ + ___ Ba₃(AsO₄)₂ is properly balanced?

A)1
B)3
C)5
D)2
E)6

Question 6

A chemical equation may sometimes be balanced with fractional coefficients.This is not appropriate when utilizing what interpretation of the reaction?

A)Macroscopic
B)Molar
C)Particulate
D)Both macroscopic and molar
E)Both molar and particulate

Question 7

12.09 g of A₂ reacts with 96.00 g of B₂ to form 108.09 g of A₂B.What is the ratio of the molar mass of A to the molar mass of B?

A)1:8
B)8:1
C)1:4
D)16:1
E)1:16

Question 8

Consider the hypothetical chemical reaction represented by the equation A + 2 B → 3 C + D Which of the following interpretations of this equation is not correct?

A)1 kg of A reacts with 2 kg of B to form 3 kg of C and 1 kg of D
B)1 particle of A reacts with 2 particles of B to form 3 particles of C and 1 particle of D
C)1 dozen particles of A reacts with 2 dozen particles of B to form 3 dozen particles of C and 1 dozen particles of D
D)1 mole of particles of A reacts with 2 moles of particles of B to form 3 moles of particles of C and 1 mole of particles of D
E)1 kilomole of particles of A reacts with 2 kilomoles of particles of B to form 3 kilomoles of particles of C and 1 kilomole of particles of D

Question 9

Consider the hypothetical chemical reaction represented by the equation 3 A + 2 B → A₃B₂ Which of the following is a correct interpretation of this equation?
i.3 grams of A react with 2 grams of B to form 1 gram of A₃B₂
ii.3 atoms of A react with 2 atoms of B to form 1 molecule of A₃B₂
iii.3 moles of A react with 2 moles of B to form 1 mole of A₃B₂

A)i only
B)ii only
C)iii only
D)ii and iii
E)i, ii, and iii

Question 10

What is the coefficient for carbon dioxide when the equation ___ C₂H₆ + ___ O₂ → ___ CO₂ + ___ H₂O is properly balanced?

A)7
B)6
C)5
D)4
E)2

Question 11

When atomic phosphorous (P)and oxygen are directly combined,P₄O₁₀ is produced.Write the balanced chemical equation for this reaction.What is the sum of the coefficients?

A)3 or less
B)5
C)7
D)9
E)10 or more

Question 12

Calcium reacts with the oxygen in the air,forming calcium oxide.Write the balanced chemical equation for this reaction.What is the sum of the coefficients?

A)3 or less
B)4
C)5
D)6
E)7 or more

Question 13

When potassium contacts fluorine gas,potassium fluoride is produced.Write the balanced chemical equation for this reaction.What is the coefficient for potassium fluoride?

A)1
B)2
C)3
D)4
E)5

Question 14

A pot of room temperature water is placed on a stovetop burner.After a couple of minutes,small,odorless,colorless bubbles form and bubble out of the liquid.After a few more minutes,similar,larger bubbles form and bubble out at a faster rate.Which of the following is the best explanation of the observations?

A)No change occurs because the bubbles contain no matter.
B)The smaller bubbles are a result of a physical change, and the larger bubbles are the result of a chemical change.
C)The smaller bubbles are the result of a chemical change, and the larger bubbles are the result of a physical change.
D)Both the smaller and larger bubbles are the result of a physical change.
E)Both the smaller and larger bubbles are the result of a chemical change.

Question 15

When the equation ___ PCl₅ + ___ H₂O → ___ H₃PO₄ + ___ HCl is properly balanced,what is the sum of the coefficients?

A)8 or less
B)9
C)10
D)11
E)12 or more

Question 16

Consider the following particulate-level representation of a chemical equation: Assume that all spheres represent atoms of A.Which of the following is a correctly balanced equation for this reaction?

A)A → 2 A
B)A₂ → 2 A
C)2 A → 2 A
D)A → 1/2 A + 1/2 A
E)A(s) → A(g)

Question 17

Ammonia is formed from its elements.Write the balanced chemical equation for this reaction.What is the sum of the coefficients?

A)3 or less
B)4
C)5
D)6
E)7 or more

Question 18

When the equation ___ Ca(OH)₂ + ___ H₃PO₄ → ___ Ca₃(PO₄)₂ + ___ H₂O is properly balanced,what is the sum of the coefficients?

A)8 or less
B)9
C)10
D)11
E)12 or more

Question 19

What is the coefficient for Zn when the equation ___ Zn + ___ H₃PO₄ → ___ H₂ + ___ Zn₃(PO₄)₂ is properly balanced?

A)1
B)2
C)3
D)4
E)6

Question 20

The following image shows the result of mixing an aqueous solution of silver nitrate with an aqueous solution of sodium chloride. The products of the reaction are a solid and a solution.The physical states of the reaction in the equation should be specified using which set of state symbols,respectively?

A)(l), (l), (s), (l)
B)(aq), (aq), (s), (aq)
C)(aq), (aq), (s), (l)
D)(l), (l), (s), (aq)
E)(aq), (aq), (p), (aq)

Question 21

Solid magnesium hydroxide is added to hydrochloric acid.Write the balanced chemical equation for this reaction.What is the sum of the coefficients?

A)4
B)5
C)6
D)7
E)8 or more

Question 22

Bromine is added to a solution of sodium iodide.Write the balanced chemical equation for this reaction.What is the sum of the coefficients?

A)4 or less
B)5
C)6
D)7
E)8 or more

Question 23

A precipitate forms when solutions of magnesium bromide and sodium hydroxide are combined.Write the balanced chemical equation for this reaction.What is the coefficient for magnesium bromide?

A)1
B)2
C)3
D)4
E)5

Question 24

Pure hydrogen iodide decomposes spontaneously to its elements.Write the balanced chemical equation for this reaction.What is the sum of the coefficients?

A)5
B)3
C)7
D)4
E)6

Question 25

Lithium combines with oxygen to form lithium oxide.Write the balanced chemical equation for this reaction.What is the coefficient for lithium?

A)4
B)3
C)2
D)1
E)none of the above

Question 26

Examine the following two beakers. When the equation for this reaction is balanced,what should the coefficient of Al?

A)1
B)2
C)3
D)4
E)6

Question 27

Molten sodium chloride is decomposed into its elements by electrolysis.Write the balanced chemical equation for this reaction.What is the sum of the coefficients?

A)3 or less
B)4
C)5
D)6
E)7 or more

Question 28

Nitric acid reacts with a solution of potassium hydroxide.Write the balanced chemical equation for this reaction.What is the sum of the coefficients?

A)10
B)8
C)6
D)4
E)none of the above

Question 29

Calcium nitrate and potassium fluoride solutions react to form a precipitate.How should this reaction be classified?

A)combination
B)decomposition
C)double-replacement
D)single-replacement

Question 30

Consider the following particulate-level representation of a reaction. How would this reaction be classified.

A)combination
B)decomposition
C)single-replacement
D)double-replacement

Question 31

Magnesium is placed into sulfuric acid.Write the balanced chemical equation for this reaction.What is the sum of the coefficients?

A)4 or less
B)5
C)6
D)7
E)8 or more

Question 32

A precipitate forms when magnesium chloride and sodium fluoride solutions are combined.Write the balanced chemical equation for this reaction.What is the sum of the coefficients?

A)6
B)5
C)4
D)9
E)none of the above

Question 33

Calcium reacts with hydrobromic acid.Write the balanced chemical equation for this reaction.What is the sum of the coefficients?

A)4 or less
B)5
C)6
D)7
E)8 or more

Question 34

When sodium chloride and silver nitrate solutions are combined,the reaction shown below occurs. Write the balanced chemical equation for this reaction.What is the coefficient for silver nitrate?

A)5
B)4
C)3
D)2
E)1

Question 35

Barium peroxide,BaO₂,breaks down into barium oxide and oxygen.Write the balanced chemical equation for this reaction.What is the coefficient for barium oxide?

A)3
B)1
C)5
D)4
E)2

Question 36

A piece of potassium is placed in a phosphoric acid solution.Write the balanced chemical equation for this reaction.What is the coefficient for potassium?

A)1
B)2
C)3
D)4
E)none of the above

Question 37

Solid aluminum is dropped into a solution of sulfuric acid.Write the balanced chemical equation for this reaction.What is the coefficient for sulfuric acid?

A)1
B)2
C)3
D)4
E)5

Question 38

Consider the following particulate-level representation of a reaction How is the reaction classified?

A)combination
B)decomposition
C)single-replacement
D)double-replacement

Question 39

Lead (II)carbonate decomposes to lead (II)oxide and carbon dioxide.Write the balanced chemical equation for this reaction.What is the coefficient for lead (II)carbonate?

A)1
B)2
C)3
D)4
E)5

Question 40

The combination of copper (II)nitrate and ammonium sulfide solutions yields a precipitate.Write the balanced chemical equation for this reaction.What is the coefficient for copper (II)nitrate?

A)3
B)1
C)5
D)2
E)4

Question 41

Phosphoric acid reacts with sodium hydroxide.Write the balanced chemical equation for this reaction.What is the coefficient for sodium hydroxide?

A)3
B)6
C)2
D)1
E)4

Question 42

Sulfuric acid neutralizes a barium hydroxide solution.Write the balanced chemical equation for this reaction.What is the sum of the coefficients?

A)4
B)5
C)6
D)7
E)8 or more

Question 43

Calcium hydroxide is added to perchloric acid.Write the balanced chemical equation for this reaction.What is the coefficient for perchloric acid?

A)5
B)4
C)3
D)2
E)1

Question 44

Aluminum hydroxide is added to nitric acid.Write the balanced chemical equation for this reaction.What is the coefficient for aluminum hydroxide?

A)6
B)4
C)3
D)2
E)1