When the following chemical equation is properly balanced, the coefficient for O2 is __.

1
When the following chemical equation is properly
balanced, the coefficient for O2 is __.

• KClO3(aq) ? KCl(s) O2(g)

2
2KClO3(aq) ? 2KCl(s) 3O2(g)
1. three
3
What is the generic formula equation for a
synthesis reaction?
4
2. A B ? AB
5
When the following formula equation is balanced,
there are a total of ___ oxygen atoms on the
right-hand side.

• C2H4(g) O2(g) ? CO2(g) H2O(g)

6
3. sixC2H4(g) 3O2(g)?2CO2(g) 2H2O(g) 4
in CO22 in H2O
7
4. TRUE or FALSE

• 5 particles of Cu(NO3)2 contain 10 copper atoms.

8
5. FALSE

• There are 5 copper atoms in 5 particles of
  Cu(NO3)2

9
What is the correct phase of matter for sugar
that has been dissolved in water?
10
6. Aqueous
11
When balancing a chemical equation, the ONLY
thing that can be changed is ___.
12
7. coefficients
13
The elements sodium and oxygen would be most
likely to form a __ compound.

1. Covalent
2. Ionic
3. Metallic
4. Molecular
5. None of the above

14
8. B. Ionic because sodium is a metal and
oxygen is a nonmetal and that combination usually
forms ionic compounds
15
9. TRUE or FALSE

• The equation
• Cd(s) HCl(aq) ? CdCl2(aq) H2(g)
• Represents a double replacement reaction.

16
9. FALSE

• This equation represents a single replacement
  reaction because there is an element and a
  compound on each side of the arrow

17
The element sodium is likely to form a cation or
an anion?
18
Cationsodium, Na, has one valence electron so
it will form a cation with a 1 charge
19
In a chemical equation, the arrow is read as
___.

1. Electricity
2. Makes
3. Equals
4. Special conditions
5. Reacts to yield

20
11. E. Reacts to yield
21
12. Which of the following phases of
matter would be appropriate to represent
steam?

1. (s)
2. (l)
3. (w)
4. (g)
5. (aq)

22
12. D. (g)

• Steam is water in the vapor, or gaseous, phase of
  matter

23
13. TRUE or FALSE

• In a chemical formula, the subscripts represent
  the number of that type of atom found in one unit
  of the substance.

24
13. TRUE

• For example
• KClO3
• The subscript, 3, means there are three atoms of
  oxygen in one unit of KClO3

25
14. TRUE or FALSE

• There are a total of 91 atoms in 7 particles of
  Cu3(PO4)2

26
14. TRUE

• Cu 7 x 3 21 atoms
• P 7 x 2 14 atoms
• O 7 x 4 x 2 56 atoms
• total 91 atoms

27
The following equation represents a ___
reaction.C3H8 (g) O2 (g) ? CO2 (g)
H2O (l)

1. Combustion
2. Neutralization
3. Decompositon
4. Synthesis
5. Single replacement

28
15. A. combustion

• Look for oxygen as a reactant and water and
  carbon dioxide, CO2, as products

29
Which of the following substances is a
hydrocarbon?

1. H2O
2. CO2
3. CH4
4. CH3OH
5. NH4Cl

30
16. C. CH4

• Look for a compound composed of ONLY the atoms
  hydrogen and carbon

31
Which of the following formula equations
represents a synthesis reaction?

• A) 2CO O2 ? 2CO2
• B) 2AgNO3 Na2SO4 ? Ag2SO4 2NaNO3
• C) 2H2 O2? 2H2O
• 2C4H10 13O2? 8CO2 10H2O
• Mg(s) 2HCl ? MgCl2 (aq) H2

32
17. Both A. and C.

• Look for a reaction with two or more substances
  on the left and only one substance on the right
• A) 2CO O2 ? 2CO2
• C) 2H2 O2? 2H2O

33
When the following formula equation is correctly
balanced, there are ___ iron atoms on the
left-hand side of the equation.

• Fe(OH)3 H2SO4 ? Fe2(SO4)3 H2O

34
18. two

• 2Fe(OH)3 3H2SO4 ? Fe2(SO4)3 6H2O
• Fe 2 Fe 2
• O 6 O 6
• H 6 6 12 H 12
• SO4 3 SO4 3

35
19. TRUE or FALSE

• The following equation obeys the law of
  conservation of mass.
• Fe2O3 CO ? 2Fe CO2

36
19. FALSE

• As is, the following equation does not have an
  equal number of each kind of atom on each side of
  the arrow
• Fe2O3 CO ? 2Fe CO2
• Fe 2 Fe 2
• O 3 1 4 O 2
• C 1 C 1

37
In chemical equations, __ is/ are written above
or below the arrow.

1. Electricity
2. Reacts to yield
3. Coefficients
4. Subscripts
5. Special conditions

38
20. E. Special conditions
39
Which of the following is the correct type of
ion for barium, 56?

• A. B
• B. Ba 2
• C. Ba2
• D. Br
• E. B 8

40
21. C. Ba2

• Barium is in Group2, so it has 2 valence
  electrons..it is easier to lose 2 than to gain
  6, so Barium will lose 2 and have a 2 charge

41
The following equation is an example of a ___
reaction.Fe(OH)3 H2SO4 ? Fe2(SO4)3(aq)
H2O
42
22. Double replacement
43
Which of the elements are stable without
gaining, losing, or sharing electrons?
44
23. The Noble Gases
45
The element phosphorus wants to ___.

• A. lose 5 electrons
• B. gain 3 electrons
• C. stay the way it is
• D. lose 3 electrons
• E. gain 5 electrons

46
24. B. gain 3 electrons

• Phosphorous, 15, AND in group 15, has 5 valence
  electrons. It is easier to gain 3 than lose 5,
  so phosphorous will gain 3 electrons and become
  P 3

47
Which of the following elements will definitely
form an anion?

• A. Rubidium
• B. Carbon
• C. Oxygen
• D. Aluminum
• E. Silicon

48
25. C. Oxygen

• Rubidium will lose 1 electron, Rb1 cation
• Carbon and silicon cannot be predicted
• Aluminum will lose 3 electrons, Al3 cation
• Oxygen will gain 2 electrons, O 2 anion

49
How many oxygen atoms are in 1 unit of the
following compound?Cu(OH)2
50
26. 2 oxygen atoms
51
When the following equation is properly
balanced, there will be _____atoms of hydrogen
on the right side of the equation.C4H10 O2
? CO2 H2O
52
27. 20 H atoms

• 2C4H10 13O2 ? 8CO2 10H2O

53
28. TRUE or FALSE

• The following equation
• H2 (g) O2(g) ? H2O2 (g)
• has been properly balanced below.
• 2 H2 (g) O2(g) ? 2 H2O2 (g)

54
28. FALSE

• 2 H2 (g) O2(g) ? 2 H2O2 (g)
• H 4 H 4
• O 2 O 4

55
When the following equation is properly
balanced, how many molecules of water are
present?Na2CO3 H2SO4 ? Na2SO4 H2O CO2
56
29. one

• Na2CO3 H2SO4 ? Na2SO4 H2O CO2
• Na 2 Na 2
• C 1 C 1
• O 3 O 3
• H 2 H 2
• SO4 1 SO4 1

57
30. TRUE or FALSE

• The substance, MgBr2 is probably a covalent
  compound.

58
30. FALSE

• Mg (magnesium) is a metal from the
• far left of the periodic table.
• Br (bromine) is a nonmetal from the
• far right of the periodic table.
• Metals nonmetal usually ionic compound

59
There are __ particles of the following
substance.5 (NH4)3PO4
60
31. 5

• The coefficient determines the total number of
  the overall particle present