Name: __________________________ Date: _____________
1. A 0.500 g sample of a compound is dissolved in enough water to form 100.0 mL of
solution. This solution has an osmotic pressure of 2.50 atm at 25.0 oC. If each
molecule of the solute dissociate into two particles (in this solvent), what is the molar
mass in g/mol of this compound?
A)
B)
C)
D)
E)
97.9
48.9
51.1
25.6
82.6
2. An organic compound contains only C, H and O. When a small sample of this
compound was burned, it produced 80.8 % C, 3.85 % H and 15.4 % O.
The freezing point of camphor (solvent) is lowered by 22.3 oC, when 1.32 g of this
organic compound is dissolved in 11.4 g camphor. Determine the molecular formula of
the organic compound. [The Kf for camphor is 40.0 oC/molal]
A)
B)
C)
D)
E)
C14H8O2
C7H4O
C9H6O
C12H10O2
C6H5O
3. A mixture of ethanol and propanol behaves ideally at 36 oC and is in equilibrium with
its vapor. If the mole fraction of ethanol in the solution is 0.62, calculate its mole
fraction in the vapor phase at this temperature. (The vapor pressures of pure ethanol
and propanol at 36 oC are 108 and 40.0 mmHg, respectively)
A)
B)
C)
D)
E)
0.815
0.359
0.590
0.213
0.778
Page 1
4. The dissolution (or miscibility) of water in octane (C8H18) is prevented by ________.
A)
B)
C)
D)
E)
hydrogen bonding between water molecules
ionic forces between octane molecules
dipole-dipole attraction between octane molecules
ion-dipole attraction between water and octane molecules
repulsion between like-charged water and octane molecules
5. What is the molarity (M) of sodium chloride in solution that is 13.0% by mass sodium
chloride and that has a density of 1.10 g/mL?
A)
B)
C)
D)
E)
2.45
0.0143
143
2.56
2.23
Page 2
6. A sample of potassium nitrate (49.0 g) is dissolved in 101 g of water at 100 °C, with
precautions taken to avoid evaporation of any water. The solution is cooled to 30.0 °C
and no precipitate is observed. This solution is ________.
A)
B)
C)
D)
E)
supersaturated
unsaturated
saturated
hydrated
aquated
7. When X rays of wavelength 0.090 nm are diffracted by a metallic crystal, the angle of
first order diffraction (n = 1) is measured to be 15.2o. What is the distance (in pm)
between the layers of atoms responsible for the diffraction?
A)
B)
C)
D)
E)
172
0.0172
1.72
17.2
1720
Page 3
8. Which one of the following substances will not have hydrogen bonding as one of its
intermolecular forces?
A)
B)
C)
D) HF
E)
9.
The heating curve shown above was generated by measuring the heat flow and
temperature of a solid as it was heated. The heat flow into the sample in the segment
________ will yield the value of the ΔHvap of this substance.
A)
B)
C)
D)
E)
DE
EF
BC
AB
CD
Page 4
10. Find the temperature at which ethanol boils on a day in the mountains when the
barometric pressure is 547 mmHg. (Given: The heat of vaporization of ethanol is 39.3
kJ/mol; the normal boiling point of ethanol is 78.3°C).
A)
B)
C)
D)
E)
69.9°C
76.5°C
10.0°C
77.9°C
74.6°C
11. Metallic iron crystallizes in a cubic lattice. The unit cell edge is 287 pm. The density
of iron is 7.87 g/cm3. How many atoms are within a unit cell?
A)
B)
C)
D)
E)
2
4
1
3
5
12. Examine the phase diagram for the unknown substance bogusium (Bo) and select the
correct statement.
A)
B)
C)
D)
E)
Point B represents the critical temperature and pressure for Bo.
Bo(s) has a lower density than Bo(l).
The triple point for Bo is at a higher temperature than the melting point for Bo.
Bo changes from a solid to a liquid as one follows the line from C to D.
Bo changes from a liquid to a gas as one follows the line from C to D.
Page 5
13. A 22.4 L high pressure reaction vessel is charged with 0.3910 mol of iron powder and
1.2 atm of oxygen gas at standard temperature.
On heating, the iron and oxygen react according to the balanced reaction below.
4Fe(s) + 3O2(g) → 2Fe2O3(s)
After the reaction vessel is cooled, and assuming the reaction goes to completion, what
pressure of oxygen remains?
A)
B)
C)
D)
E)
0.91 atm
1.2 atm
0.68 atm
0.29 atm
0.20 atm
14. Which one of the following statements is true about equal volume of CH4 and O2 gases
at 20 oC and 1 atm pressure?
A) The CH4 sample has a mass that is one-half that of the O2 sample.
B) The number of O2 molecule is twice as much as the number of CH4 molecules.
C) The average kinetic energy of the O2 molecules is one-half that of the CH4
molecules.
D) The average velocity of the O2 molecules is one-half of the CH4 molecules.
E) The number of moles of O2 is twice as much as the number of moles of CH4.
15. When 73.0 g NH3 gas reacts with 73.0 g of HCl gas at a 1:1 molar ratio, they produce
NH4Cl(s). What is the volume of the remaining gas at 14.0 °C and 752 mmHg?
A)
B)
C)
D)
E)
54.4 L NH3
2.26 L HCl
4.29 L NH3
2.00 L HCl
10.7 L HCl
Page 6
16. An open–ended mercury manometer is used to measure the pressure exerted by a
trapped gas as shown in the below figure.
If the atmospheric pressure is 749 mmHg, what is the pressure of the trapped gas if the
height of Hg is 18 cm as shown in the figure?
A)
B)
C)
D)
E)
929 mmHg
749 mmHg
180. mmHg
569 mmHg
90.0 mmHg
17. The root-mean-square speed of a certain gasous oxide is 493 m/s at 20.0 oC. What is
the molecular formula of the compound? (J = kg ·m2· s-2)
A)
B)
C)
D)
E)
NO
CO
N2
CO2
N2O
18. “The pressure of a given amount of gas is inversely proportional to its volume at
constant temperature” is a statement of __________________ Law.
A)
B)
C)
D)
E)
Boyle's
Charles's
Avogadro's
Gay–Lussac's
Dalton
Page 7
19. Specific heat is an example of:
A)
B)
C)
D)
E)
Intensive property.
Extensive Property.
Chemical Intensive Property.
Physical Extensive Property.
Both intensive as well as extensive properties.
20. The term that is related to the reproducibility (repeatability) of a measurement is
A)
B)
C)
D)
E)
precision.
accuracy.
qualitative.
quantitative.
intrisic property.
21. What is the formula for lead(II) oxide?
A) PbO
B) PbO2
C) Pb2O
D) PbO4
E) Pb2O3
22. In which of the following sets are all species isoelectronics?
A)
B)
C)
D)
E)
-
2+
F , Ne, Mg
2Ge, Se , Br
+
+
+
K , Rb , Cs
+
Br, Br , Br
+
+
O , F , Cs
23. How many hydrogen atoms are there in 12.4 g of Al2(HPO4)3?
A)
B)
C)
D)
E)
22
6.55 × 10
22
1.09 × 10
22
6.07 × 10
23
1.32 × 10
22
4.39 × 10
H atoms
H atoms
H atoms
H atoms
H atoms
Page 8
24. A 4.05 g sample of a compound containing only C, H, and O was burned completely.
The only combustion products were 10.942 g CO2 and 4.476 g H2O. What is the
empirical formula of the compound?
A)
B)
C)
D)
E)
C7H14O
C7H7O
C7H14O7
CH2O
C6H12O
25. How many grams of aluminium oxide will be produced when 5.71 gram of aluminium
(Al) reacts with excess oxygen molecules?
A)
B)
C)
D)
E)
10.8
9.06
5.40
4.53
18.1
26. A sample of 0.4307g of an unknown compound containing silver ions (Ag+) is dissolved
in water and treated with an excess of NaCl. If the mass of the AgCl precipitate formed
is 0.3105 g, what is the percent by mass of Ag in the original unknown compound?
A)
B)
C)
D)
E)
54.27 %
35.70 %
73.42 %
24.84 %
82.13 %
27. The oxidation number of N in N2H4 is
A)
B)
C)
D)
E)
-2
+2
+4
-4
+1
Page 9
28. What substance is oxidized in the following chemical reaction?
NiO2 + Cd + 2H2O  Ni(OH)2 + Cd(OH)2
A)
B)
C)
D)
E)
Cd
Ni
O
H
NiO2
29. If a reaction is carried out at constant pressure, which one of the following statements is
correct?
A)
B)
C)
D)
E)
The heat change is equal to the enthalpy change.
The reaction is likely to be exothermic
The reaction is likely to be endothermic.
The heat change is equal to the change in temperature.
The heat change is equal to the internal energy.
30. Which one of the following statements about quantum theory is incorrect?
A) When filling orbitals with the same n and l quantum numbers, two electrons will
fill the same ml before filling a new ml.
B) Lower energy orbitals are filled with electrons before higher energy orbitals.
C) No two electrons can have the same four quantum numbers in the same atom.
D) Valence electrons are in higher energy quantum levels than inner shell (core)
electrons.
E) Electrons will follow Hund's rule in filling degenerate orbitals.
31. Which match is incorrect?
A)
B)
C)
D)
E)
Thomson / demonstrated the existence of the neutron
Millikan / determined the magnitude of the charge on an electron
Rutherford / showed that most of the mass of an atom is in its nucleus
de Broglie / predicted that electrons have wave-like properties
Planck / proposed that radiant energy could only be absorbed or emitted in discrete
quantities
Page 10
32. Which of the following are p-block elements?
A)
B)
C)
D)
E)
Pb, Ca, Kr, La, O
Pb, Kr and O only
Kr, La and O only
Kr and O only
Ca, Kr, La and O only
All of them
33. Which of the following is (are) diamagnetic.
A)
B)
C)
D)
E)
IV only
I and II only
I, II and III only
II and IV only
All of the them
34. How many pi bonds and sigma bonds are there in following structure?
A)
B)
C)
D)
E)
3 pi bonds and 10 sigma bonds.
5 pi bonds and 8 sigma bonds.
5 pi bonds and 10 sigma bonds.
8 pi bonds and 5 sigma bonds.
2 pi bonds and 12 sigma bonds.
35. Determine the number of electron domains around the central atom and molecular
geometry of ClF3.
A)
B)
C)
D)
E)
5 electron domains, T-shaped.
3 electron domains, T-shaped.
4 electron domains, tetrahedral.
4 electron domains, trigonal pyramidal.
6 electron domains, octahedral.
Page 11
36. One resonance structure for OCN– ion is drawn below. What is the formal charge on
each atom?
A)
B)
C)
D)
E)
O atom = –1, C atom = 0, and N atom = 0
O atom = 0, C atom = 0, and N atom = –1
O atom = 0, C atom = -1, and N atom = 0
O atom = –1, C atom = –1, and N atom = +1
O atom = +1, C atom = 0, and N atom = –2
37. What is the bond angle between F-Xe-F in XeF2 molecule?
A)
B)
C)
D)
E)
180o
90o
120o
109.5o
60o
38. In the following reaction, aluminum reduces iron(III) oxide to elemental iron:
2Al(s) + Fe2O3(s)  2Fe(s) + Al2O3(s)
H = –850 kJ
What mass of iron is formed when 725 kJ of heat are released?
A)
B)
C)
D)
E)
95 g
47 g
65 g
112 g
130 g
39. Which one of the following statements is correct for the NO3- ion?
A)
B)
C)
D)
E)
All the three N-O bonds have the same bond length.
It has one localized pi bond and three sigma bonds.
It has two localized pi bonds and three sigma bonds.
It has only two resonance structures.
It has no resonance structure.
Page 12
40. What is the hybridization of As in AsCl4+ ion?
A)
B)
C)
D)
E)
sp3
sp2
sp
sp3d
sp3d2
Page 13
Answer Key
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
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