Download Chem 201A Question 2

Question 1
Which of the following is a chemical change?
Chem 201A
Final Exam Review
a. Aluminum can crushed by air pressure
b. Melting of ice
c. Heat from a stove flows through an aluminum pan to
the water inside
d. The silver spoon used to eat eggs turns black
Correct answer is
d
Question 3
Question 2
How much energy is available if 0.00145 mol of
photons are emitted at 295 nm?
h = 6.626 x 10-34 Jxs
a. 5.88 x 102 J
b. 4.05 x 105 J
c. 1.02 x 1015 J
d. 6.74 x 10-19 J
Correct answer is
a
Which of the following is (are) elements?
i) CO
ii) Co
iii) C
iv) Cl2
a.
b.
c.
d.
e.
v) CaCl2
only iii
iii and iv
i and v
ii, iii and iv
ii and iii
Correct answer is
d
Question 4
Question 5
The correct formula of potassium sulfate is
The correct formula of ammonium carbonate is
a. K2SO3
b. K2S
c. KHSO4
d. K(SO4)2
e. K2SO4
a. N2CO3
b. (NH4)2CO3
c. NH4CO3
d. (NH3)2CO3
e. (NH4)4C
Correct answer is
e
Correct answer is
b
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Question 6
Question 7
What’s the empirical formula of a compound consisting of
45.27% carbon,
9.49% hydrogen, and
45.23% oxygen by mass? (Assume 100g of compound).
Which is the best pair of solvents for decanoic acid,
CH3(CH2)8CO2H
a.
b.
c.
d.
C5H9O4
C4H9O3
C45H9O45
C4H10O3
Correct answer is
a. kerosene
b. kerosene
c. ethanol
d. ethanol
e. water
d
or
or
or
or
or
aqueous NaOH
aqueous HCl
water
aqueous NaCl
aqueous NaOH
Correct answer is
a
Question 8
Question 9
Name the binary compounds PCl5 and S2Cl2.
Write the name for Mg(NO3)2 and the formula of
cobalt (II) chloride hexahydrate.
Are they molecular or ionic?
a. Phosphorus pentachloride
b. Phosphorus chloride
c. Phosphorus (V) chloride
d. Phosphorus pentachloride
Correct answer is
and
and
and
and
disulfur dichloride.
disulfur dichloride.
disulfur dichloride.
sulfur (II) chloride.
a. Magnesium (II) Nitrite,
b. Magnesium (II) Nitrate,
c. Magnesium Nitrate,
d. Magnesium Nitrate,
a
Correct answer is
CoCl2*6H2O.
CoCl2*6H2O.
CoCl2*6H2O.
CoCl2*6H2O.
Ionic.
Molecular.
Ionic.
Molecular.
c
Question 10
Question 11
The element Rhenium, Re, has two stable isotopes and 18
unstable isotopes. Re-185 has in its nucleus:
What mass of CO2 (MM 44.01 g/mol) is formed in the
reaction of 233 g of Fe2O3 (MM 159.7 g/mol)
with 41.2 g C(s), given the following equation:
a. 75 protons, 75 neutrons
b. 75 protons, 111 neutrons
c. 130 protons, 75 neutrons
d. 75 protons, 110 neutrons
e. 185 protons, 185 neutrons
Correct answer is
d
a.
b.
c.
d.
3 C(s)
64.2 g
48.1 g
96.3 g
2.19 g
+ 2 Fe2O3(s)  4 Fe(s)
Correct answer is
+ 3 CO2(g)
c
2
Question 12
Question 13
When 1.50 mol of oxygen gas is mixed with 48.7 g of zinc
sulfide, the products are solid zinc oxide and sulfur
dioxide gas. How many moles of zinc oxide could form
in this reaction.
Which aqueous solution will have the highest
concentration of dissolved particles?
a.
b.
c.
d.
0.50 mol
1.5 mol
2.0 mol
1.0 mol
Correct answer is
a
i
tetrahedral, trigonal pyramidal, trigonal pyramidal
trigonal pyramidal, trigonal pyramidal, trigonal pyramidal
tetrahedral, trigonal planar, trigonal pyramidal
tetrahedral, trigonal planar, trigonal planar
trigonal planar, trigonal planar, trigonal planar
a.
b.
c.
d.
6 mol
2 mol
5 mol
3 mol
Correct answer is
a
Question 17
For a complete reaction of
Mg (s) + Ge (s)  MgGe (s),
(balanced)
about what mass ratio of the elements should be used?
the masses of Mg and Ge will be equal
the mass of Mg will be ½ the mass of Ge
the mass of Ge will be ½ the mass of Mg
the mass of Mg will be three times the mass of Ge
the mass of Ge will be three times the mass of Mg
Correct answer is
If 3 moles of calcium hydroxide are reacted with excess
HCl, how many moles of H2O will be produced?
c
Question 16
a.
b.
c.
d.
e.
b
Question 15
The molecular geometries of central
atoms, from left to right, are..?
Correct answer is
1.00 mol of NaCl in 1.0 L
1.50 mol of NaCl in 0.5 L
3.00 mol of methanol in 1.0 L
3.00 mol of CaCl2 in 2.0 L
Correct answer is
Question 14
a.
b.
c.
d.
e.
a.
b.
c.
d.
e
How much energy does a refrigerator have to remove
from 1.50 kg of water at 20.0 C to cool the water to
2.00 C? Specific heat of water = 4.18 J/g C.
a.
b.
c.
d.
e.
126 J
113 J
1.13x105 J
1.26x105 J
none of the above
Correct answer is
c
3
Question 18
Question 19
In the lab, a student filled a 500.0 mL container with an
unknown gas until a pressure of 380.0 torr was
obtained when the temperature was 25 ºC. He then
found that the sample of gas weighed 0.164 g. What
is the molar mass of the gas?
Calculate the H for the synthesis of propane
3 C (s) + 4 H2 (g)  C3H8 (g)
a.
b.
c.
d.
e.
1.34 g/mol
16.0 g/mol
62.3 g/mol
0.0211 g/mol
1.77×10-3 g/mol
Correct answer is
C3H8(g) + 5O2(g)  3CO2(g) + 4H2O(l) H = -2220 kJ
C (s) + O2 (g)  CO2 (g)
H = -394 kJ
H = -286 kJ
H2 (g) + ½ O2 (g)  H2O (l)
a - 106 kJ
b
b. 106 kJ
Correct answer is
c. 1540 kJ
d. -212 kJ .
a
Question 20
Question 21
Which pair [or pairs] of solutions will give a precipitate
when mixed?
What is the pH of a 0.00873 M solution of Ba(OH)2?
a.
b.
c.
d.
AgNO3(aq)
Na2CO3(aq)
Fe(NO3)2(aq)
NaOH(aq)
a.
b.
c.
d.
and NaC2H3O2(aq)
and Ca(ClO4)2(aq)
and NaCl(aq)
and CuCl2(aq)
Correct answers are b
and d
Correct answer is
How many mL of a 3.59 M solution are needed to
make 250.0 mL of a 0.925 M solution?
13.3 mL
A 3.00 g sample of copper (II) sulfate pentahydrate
(MM of CuSO4 is 159.7 g/mol) is heated until it turns
white. What is the mass of the final solid product?
a.
b.
c.
d.
e.
b. 64.4 mL
c.
c
Question 23
Question 22
a.
2.06
1.75
12.25
11.94
970 mL
d. 15.5 mL
Answer is
1.92 g
2.19 g
2.78 g
2.23 g
1 .87 g
Answer is
a
b
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Question 24
Using the above MO scheme, what is the
bond order of CN–? (show with fingers)
Using the above MO scheme, what is the
bond order of CN–?
B.O. = 3
Question 25
A 25.00 mL sample of sulfuric acid is titrated with 23.59
mL of 0.4159 M NaOH. What is the concentration of
the acid?
a.
b.
c.
d.
• End of review:
• 1 more slide for tiebreaker
0.3924 M
0.7848 M
0.004906 M
0.1962 M
Answer is d
Tie-Breaker Question:
Question 25
How much energy must be absorbed to turn 6.00 pounds
of ice at -5.0 ºC to water at 20.0 ºC. 1 kg = 2.205 lb
Hvap = 40.7 kJ/mol
Hfusion = 6.09 kJ/mol
Cs ice = 2.09 J/(g ºC)
A 25.00 mL sample of sulfuric acid is titrated with 23.59
mL of 0.4159 M NaOH. What is the concentration of
the acid?
a.
b.
c.
d.
e.
1.26x106 kJ
4.35x104 kJ
1.17x103 kJ
7950 kJ
688 kJ
Answer is c
a.
b.
c.
d.
0.3924 M
0.7848 M
0.1962 M
0.004906 M
Answer is c
5
Name these molecular shapes
Name these molecular shapes
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