Download Reactions Practice Problems

Reactions Practice Problems
1) The electrolysis of water (shown below) takes place when an electric current is passed through
water. It is an example of a __________ reaction (select all that apply).
2H2O
electricity
1)
2H2 + O2
A) single displacement
B) double displacement
C) combustion
D) decomposition
E) redox
2) The following reaction is an example of a __________ reaction (select all that apply).
A) single displacement
B) double displacement
C) combustion
D) decomposition
E) redox
2C2H6 + 7O2
4CO2 + 6H2 O
3) The following reaction is an example of a __________ reaction.
A) combustion
B) single displacement
C) double displacement
D) decomposition
E) redox
NaH + H2 O
2)
3)
NaOH + H2
4) Which of the following is a combination reaction?
H2 O + KNO3
A) KOH + HNO3
4)
5) Which of the following represents a neutralization reaction?
A) 2 H2(g) + O2 (g) 2 H2 O(l)
B) 2 H2O2 (aq) 2 H2 O(l) + O2(g)
C) 2 NaOH(aq) + CuCl2 (aq) 2 NaCl(aq) + Cu(OH)2 (s)
D) LiOH(aq) + HCl(aq) LiCl(aq) + H2O(l)
5)
AgCl + NaNO3
B) AgNO3 + NaCl
Al2 (SO4 ) 3 + H2
C) Al + H2 SO4
2Al(OH)3 + 3K2 SO4
D) Al2 (SO4 )3 + 6KOH
2NO
E) N2 + O2
E) HBr(aq) + AgNO3 (aq)
HNO3 (aq) + AgBr(s)
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6) Which of the following represents a single displacement reaction?
PbCl2 + 2NaNO3
A) Pb(NO3)2 + 2NaCl
MgSO4 + 2NaCl
B) Na2SO4 + MgCl2
6)
BaSO4 + 2KCl
C) K2 SO4 + BaCl2
2NO
D) N2 + O2
ZnSO4 + H2
E) Zn + H2 SO4
7) Balance the following reaction:
C4 H10 +
7)
O2
CO2 +
H2 O
8) Balance the following reaction:
N2H4 +
8)
H2O2
N2 +
H2 O
9) Write and balance the equation that describes the reaction of aqueous silver nitrate and
potassium chloride, if one occurs:
9)
10) Write and balance the equation that describes the reaction of aluminum metal and sulfuric
acid, if one occurs:
10)
11) Write and balance the equation that describes the reaction of aqueous potassium
phosphate and calcium nitrate, if one occurs:
11)
12) Potassium superoxide solid reacts with carbon dioxide gas to form solid potassium
carbonate and oxygen gas. Write and balance the equation that describes this reaction:
12)
13) Write and balance the equation that describes the combustion of butanethiol
(CH3 CH2 CH2CH2 SH):
13)
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14) Which of the following compounds is essentially insoluble in water and will form a gas when HCl
is added to water containing the solid compound?
A) K2 SO4
B) CaCO3
C) K2 CO3
D) AgCl
E) CaSO4
15) Which reagent below would be the best choice to separate the CATIONS in the mixtures that follow:
a) water
b) NaOH(aq)
c) HCl(aq)
d) Na2 CrO4(aq)
1) PbSO4(s) + Cu(NO3)2(s)
________________
2) Mg(OH)2(s) + BaSO4(s)
________________
1) PbCO3(s) + CaCO3(s)
________________
d) BaCl2(aq)
16) How many milligrams of hydrogen gas can be produced if 1.005 millimoles of sulfuric acid
reacts with an excess amount of zinc metal. Assume all hydrogen can be converted to
hydrogen gas.
16)
17) A piece of aluminum foil measuring 5.23 cm x 7.98 cm x 0.245 mm is completely dissolved
in a solution of HCl. How many milligrams of hydrogen gas are produced? (The density of
aluminum is 2.70 g/cm3)
17)
18) Using the following unbalanced equation, how many mg of water will be required when
2.50 mg of magnesium nitride is allowed to react?
18)
Mg3N2 +
H2 O
Mg(OH)2 +
3
NH3
14)
19) How many milligrams of CO2 will be produced if 125.0 mg of methane burn in a container
with 150.0 mg of O2 ?
19)
20) In the reaction of nitrogen gas with hydrogen gas to form ammonia gas how many grams of
ammonia will be produced if 6.97 grams of nitrogen gas are allowed to react with 2.82 grams of
hydrogen gas?
20)
A) 8.47 g
B) 2.00 g
C) 15.88 g
D) 2.17 g
E) this problem is impossible to solve
21) If you recover 7.00 g in the above exeperiment, what is your percent yield?
A) 97%
B) 34.0%
C) 76.5%
22) Calculate the molarity of Cl- in 245.0 mL of a solution containing 23.4 g BaCl 2 (208.24
amu).
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21)
D) 82.6%
22)
23) What will the molar concentration of all ions be if you dissolve 45.6782 g of magnesium
sulfate heptahydrate (246.476 amu) in water and then bring the final volume to 500.0 mL?
23)
24) The concentration of Na+ in a 250.0 mL aqueous solution of sodium sulfate (142.043 amu)
is 0.320 M. How many grams of sodium sulfate were dissolved to prepare this solution?
24)
25) You prepare a 1.00 L solution containing 85.5 g Al2 (SO4)3 (342.15 amu) and 21.3 g Na2 SO4 (142.043 amu).
What are the molar concentrations of aluminum, sodium, and sulfate ions?
[Al3 +] =
[Na+] =
[SO42-] =
26) What volume of mthanol (32.042 amu) is required to prepare 1.50 L of a 0.250 M solution of
methanol? (The density of methanol is 0.792 g/mL)
26)
27) What mass of (110.98 amu) calcium chloride ( in grams is required to make exactly 25.00 L
of a solution that is exactly 300 µM?
27)
28) How many mL of a 5.925 M solution of nitric acid are required to make 250.00 mL of a
0.250 M solution of nitric acid?
28)
29) How many mmols of sodium are in 35.89 mL of a 0.1234 millimolar (mM) solution of
sodium phosphate?
29)
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30) How many grams of hydrogen gas will be produced if 15.00 g of aluminum metal is
immersed in 125.00 mL of a 0.238 M solution of sulfuric acid?
30)
31) If you get a 45% yield in the above reaction, how many grams of gas will you have
collected.
31)
32) How many milligrams of precipitate can be collected if 25.00 mL of a 0.275 M solution of
sodium phosphate is mixed with 25.00 mL of a 0.1875 M solution of copper(II)sulfate?
32)
33) How many millimoles of carbon dioxide will be produced if 109.3 mg of dimethyl propane
is burned in the presence of 1.096 g of oxygen?
33)
34) How many mg of dimethyl propane or oxygen will be in excess in the above reaction after
combustion?
34)
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35) What is represented by the following equation?
Na+(aq) + e-
Na(s)
36) What are the oxidation states of the underlined elements?
A) Cr2 O72B) MnO4C) NO3-
D) SO42-
36)
E) NH4+
37) What is the oxidation state of oxygen in the following molecules or ions?
oxygen gas
_______________
oxide ion
_______________
superoxide ion
_______________
peroxide ion
_______________
ozone
_______________
oxygen difluoride
_______________
38) What is oxidized and what is reduced in the following reaction?
2Al + 3Br2
2AlBr3
39) What is oxidized and what is reduced in the following reaction?
Fe2 O3 + 2Al
Al2O3 + 2Fe
40) What is oxidized and what is reduced in the following reaction?
2H2 + O2
2H2 O
41) What are the oxidizing and reducing agents in the following reaction?
2Mg + O2
2MgO
42) What are the oxidizing and reducing agents in the following reaction?
2 NO2(g) + 7 H2(g)
2 NH3(g) + 4 H2O(g)
43) How many electrons are required to reduce/oxidize (circle one) chlorine gas to chloride ions?
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44) What are the balanced oxidation and reduction half reactions in the following unbalanced reaction? What is
the net ionic equation?
Al +
H2SO4
Al2(SO4) 3 +
H2
45) (TRUE or FALSE) The following reaction is an example of a disproportionation (one substance is
both oxidized and reduced):
2 H2O2 (aq)
2 H2 O(l) + O2(g)
46) Is the following reaction spontaneous in the forward direction?
Mg(s) + AgNO3 (aq)
Ag+(aq) + eAg(s)
Mg2+(aq) + 2 eMg(s)
Ag(s) + Mg(NO3 )2(aq)
E° = 0.80 V
E° = -2.38 V
47) Is the following reaction spontaneous in the forward direction?
Pb2+ (aq) + Cu(s)
Pb2+(aq) + 2 eCu2+ (aq) + 2 e-
Pb(s)
Cu(s)
Cu2+(aq) + Pb(s)
E° = -0.13 V
E° = +0.34 V
48) Is the following reaction spontaneous in the forward direction?
3Cu(s) + 2Al(NO3)3(aq)
Al3+(aq) + 3 eCu2+ (aq) + 2 e-
Al(s)
Cu(s)
2Al(s) + 3Cu(NO3 )2(aq)
E° = -1.66 V
E° = +0.337 V
49) Is the following reaction spontaneous in the forward direction?
2Fe3+(aq) + Zn(s)
Fe3+(aq) + eFe2+(aq)
Zn2+ (aq) + 2 eZn(s)
2Fe2+ (aq) + Zn2+(aq)
E° = 0.77 V
E° = -0.76 V
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45)
50) Balance the following reaction that occurs in acidic solution. Is this reaction spontaneous in the forward
direction?
Cr2+(aq) + O2 (g)
Cr3+(aq)
O2 (g) + 4H+ (aq) + 4e- 2H2 O(l)
Cr3+(aq) + e- Cr2+(aq)
E° = 1.23 V
E° = -0.42 V
51) Balance the following reaction that occurs in basic solution?
Cr3+ + O2 2-
CrO42-
52) Balance the following reaction that occurs in acidic solution?
SO32- + MnO4 -
SO42- + Mn2+ + H2O
53) Balance the following reaction that occurs in basic solution?
Br2 + Mn2+
MnO2 + Br-
54) Balance the following reaction that occurs in acidic solution?
Zn(s) + Cr2 O72- (aq)
Zn2+ (aq) + Cr2+ (aq)
55) Balance the following reaction that occurs in acidic solution?
HCl + H2 C2O4 + MnO2 (s)
MnCl2 + CO2 (g) + H2O
56) Balance the following reaction that occurs in acidic solution?
IO3 - + N2 H4
I- + N 2
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57) Balance the following reaction that occurs in acidic solution?
C2 O42- (aq) + MnO4- (aq)
CO2 (g) + Mn2+ (s)
58) Balance the following reaction that occurs in acidic solution?
Na2C2 O4 (aq) + KMnO4 (aq)
CO2 (aq) + Mn2+ (s)
59) Balance the following reaction that occurs in basic solution?
C2 O42- (aq) + MnO4- (aq)
CO3 2- (aq) + MnO2 (s)
60) Balance the following reaction that occurs in acidic solution
VO2+ (aq) + Cr2 O7 2- (aq)
Cr3+ (aq) + VO2+ (aq)
61) Balance the following reaction that occurs in basic solution?
Al (s) + ClO- (aq)
Al(OH) 4- (aq) + Cl- (aq)
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62) Ballance the following equation that occurs in acidic solution. How many milliliters of a 3.85 M solution of Fe2+
2are needed to titrate 250.0 mL of a 0.125 M CrO 4 solution?
CrO4 2- + Fe2+
Fe3+ + Cr2 O3
(not balanced)
63) How many grams of commercially available acetic acid (97% by mass) should be measured
out to produce 75 g of acetyl chloride (CH3COCl, 78.498 g/mol) in the following process
which has a 78.2% yield?
3 CH3 COOH + PCl3
3 CH3 COCl + H3PO3
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63)
64) What mass of melamine (C3 N3 (NH2 )3) in kg can be obtained from 150.0 kg of urea (CO(NH2 )2 ) in the
following unbalanced consecutive reactions if the overall yield of this process is 78.0%?
(CO(NH2 )2 = 60.056 amu, C3 N3(NH2)3 = 126.121 amu)
RXN 1:
CO(NH2)2(l)
RXN 2:
HNCO(l)
HNCO(l) + NH3(g)
C3 N3 (NH2)3(l) +
CO2(g)
65) Write out and balance the reaction from the following description:
Reduction of vanadyl ion (VO2+) to vanadic ion (V3+ ) by zinc metal in an acidic solution.
66) Write out and balance the reaction from the following description:
Oxidation of methanol by chlorate in an acidic solution producing gaseous carbon dioxide and chlorine
dioxide.
67) What are the molarities of the following solutions:
29.6 mg K+ per 100 mL solution.
200.0 µg of methanol per mL of solution.
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