Download avogadro exam 1994 - University of Waterloo

AVOGADRO EXAM 1994
UNIVERSITY OF WATERLOO
DEPARTMENT OF CHEMISTRY
19 MAY 1994
TIME: 75 MINUTES
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Teacher
H
He
Li
Be
B
C
N
O
F
Ne
Na
Mg
Al
Si
P
S
Cl
Ar
K
Ca
Sc
Ti
V
Cr
Mn
Fe
Co
Ni
Cu
Zn
Ga
Ge
As
Se
Br
Kr
Rb
Sr
Y
Zr
Nb
Mo
Tc
Ru
Rh
Pd
Ag
Cd
In
Sn
Sb
Te
I
Xe
Cs
Ba
La*
Hf
Ta
W
Re
Os
Ir
Pt
Au
Hg
Tl
Pb
Bi
Po
At
Rn
Fr
Ra
Ac**
* Lanthanides
** Actinides
1. Which element is NOT in the same group as neon?
A
Argon
B
Boron
C
Krypton
D
Radon
E
Xenon
4. In the periodic table, the elements are arranged in
order of increasing
A
Number of neutrons
B
Number of protons
C
Ionization energy
D
Density
E
Electronegativity
2. Which terms on the left correctly match the
materials on the right?
5. Select the element that is a typical nonmetal:
Q Mechanical mixture
X Salt water
R Solution
Y Carbon dioxide
T Pure substance
Z Washing detergent
A
Silver
B
Calcium
C
Chromium
A
QX, RY, TZ
D
Sulfur
B
QX, RZ, TY
E
Einsteinium
C
QY, RX, TZ
D
QZ, RX, TY
E
QZ, RY, TX
6. Choose the element that is a solid at room
temperature and pressure:
3. Two particles with equal numbers of positive
charges repel each other with a force, F. If the
distance between the particles is doubled, the new
repulsive force will be
A
F/4
B
F/2
C
F
D
2F
E
4F
2 / AVOGADRO EXAM
 1994 UNIVERSITY OF WATERLOO
A
Argon
B
Bromine
C
Chlorine
D
Selenium
E
Krypton
7. Which molecule shows covalent bonding, with the
10. The following electronic configuration applies to an
neutral atom or a cation:
least ionic character?
1s2 2s2 2p6 3s2 3p6 4s1
A
F−
− Be−
−F
B
F−
− Li
A
An argon ion
C
F−
− Br
B
A neutral potassium atom
D
F−
−F
C
A chloride ion
E
F−
− O−
−F
D
A neutral calcium atom
E
A strontium ion
The element or ion could be
8. Which pair of characteristics applies to typical ionic
solids?
A
Good electrical conductivity and high ionization
energy
B
High melting point and malleability
C
High melting point and crystalline structure
D
Low melting point and high heat conductivity
E
Low melting point and low aqueous solubility
11. What volume of hydrogen will have nearly the
same number of molecules as 1.00 L of nitrogen
gas, if both are measured at the same
temperature and pressure?
A
0.500 L hydrogen
B
1.00 L hydrogen
C
2.00 L hydrogen
D
14.0 L hydrogen
E
28.0 L hydrogen
9. Which neutral halogen atom has the smallest
ionization energy for the first electron removed?
12. At what temperature is the average kinetic energy
A
Fluorine
B
Chlorine
C
Bromine
D
Iodine
E
Astatine
of molecules in a gas twice as great as at O°C?
A
1092 K
B
746 K
C
546 K
D
273 K
E
137 K
 1994 UNIVERSITY OF WATERLOO AVOGADRO EXAM / 3
13. Pure oxygen gas in a closed container of fixed
16. If the following equation is obeyed, how many
moles of ammonia are needed to produce
801 mol of hydrogen, H2?
volume is heated until the average energy of the
gas molecules is doubled. Which other aspect of
this system is also doubled?
→ N2(g) + 3 H2(g)
2 NH3(g)
A
The density of the oxygen
A
2.00 mol
B
The average velocity of the oxygen molecules
B
C
The density of the oxygen gas
C
267 mol
D
The pressure in the container
D
534 mol
E
The volume occupied by each oxygen molecule
E
1203 mol
22.4 mol
17. Hydrogen gas is a product in one of the following
14. What volume of argon gas at 100 kPa and 25°C
must be added to a 1.00-Litre glass flask
containing nitrogen gas at 70 kPa and 25°C to
give a mixture of gases having a total pressure of
210 kPa at 25°C?
cases. Which one?
A
Aluminum turnings are heated with hot,
concentrated potassium hydroxide solution
B
Aqueous hydrogen peroxide is added to an
aqueous solution of iron(III) nitrate
C
Solid sodium carbonate is added to dilute,
aqueous hydrochloric acid
A
1.40 L
B
1.70 L
C
2.00 L
D
Copper is placed in dilute, aqueous nitric acid
D
2.86 L
E
Calcium oxide is warmed with ammonium chloride
E
3.10 L
18. Which atom or ion is formed as a result of
15. In which of the following substances, all at
reduction in the following reaction?
100 kPa, is the average translational energy of the
molecules the greatest?
2 KMnO4 + 16 HCl →
2 KCl + 2 MnCl2 + 5 Cl2 + 8 H2O
A
Iron at 150°C
A
Potassium in KCl
B
Oxygen at 100°C
B
Manganese in MnCl2
C
Liquid water at 80°C
C
Hydrogen in H2O
D
Carbon dioxide at 70°C
D
Chlorine in Cl2
E
Ice at 0°C
E
Oxygen in H2O
4 / AVOGADRO EXAM
 1994 UNIVERSITY OF WATERLOO
19. What is the missing term, X, in the following
22. Which one of the following aqueous reagents will
most effectively remove carbon dioxide from an
air sample?
chemical equation?
238
U →
92
234
Th + X
90
A
A positron
A
Amonium nitrate solution
B
A proton
B
Silica gel
C
A neutron
C
Concentrated sulfuric acid
D
A helium nucleus
D
Sodium hydroxide solution
E
An electron
E
Sodium hydrogen carbonate solution
23. What products will result from adding solid barium
oxide to water?
20. Which set of oxidation numbers is correct for
K2Cr2O7?
A
A solution of barium hydroxide
A
K +1;
Cr +2.5;
O −1
B
Barium ions and hydrogen gas
B
K +4;
Cr +3;
O −2
C
Barium ions and oxygen gas
C
K +1,
Cr +6;
O −2
D
Barium metal and hydrogen gas
D
K +2;
Cr +12;
O −14
E
No chemical change will take place
E
K +1;
Cr +7;
O −2
24. The general formula for the binary hydrogen
compounds of the elements, E, of the nitrogen
group of the periodic table is
21. The main gaseous product of the reaction of
aqueous hydrochloric acid with manganese
dioxide is
A
EH5
B
EH4
A
Permanganic acid
C
EH3
B
Hydrogen
D
EH2
C
Chlorine
E
E2H6
D
Oxygen
E
Manganese chloride
 1994 UNIVERSITY OF WATERLOO AVOGADRO EXAM / 5
25. The percentage, by mass, of oxygen in
28. The relative molecular mass of a gas is 56.0, and
its simplest formula is CH2. What is the correct
molecular formula for the gas?
pitchblende, U3O8, is
Relative atomic masses: O, 16.00; U, 238
A
72.7%
B
35.0%
C
30.4%
D
17.9%
E
15.2%
Relative atomic masses:
26. How many moles of H2O are there in 1.8 L of
A
CH2
B
C2H4
C
C3H6
D
C4H8
E
C6H12
111 mol
B
100 mol
C
55.5 mol
D
18 mol
E
the addition of 0.0500 mol/L KOH. What is the
hydrogen ion concentration after 50.0 mL of KOH
solution has been added?
1.8 mol
27. An oxide of nitrogen contains 30.4% nitrogen, by
A
6.5 x 10−3 mol/L
B
3.3 x 10−3 mol/L
C
0.0311 mol/L
D
0.0200 mol/L
E
0.0120 mol/L
30. If, suddenly, 10.0% of the hydrogen (H) atoms on
Earth became deuterium (D) atoms, what would
be the new relative atomic mass for the element
hydrogen?
mass, and its relative molecular mass is near 90.
Which oxide of nitrogen is it?
Relative atomic masses:
H, 1.01; N, 14.0; O, 16.0
Relative atomic masses: H, 1.008; D, 2.014
A
N2O5
A
1.008
B
N2O4
B
1.109
C
N3O3
C
1.210
D
N4O2
D
1.512
E
NH4NO3
E
2.014
6 / AVOGADRO EXAM
H, 1.0
29. 40.0 mL of 0.0700 mol/L aqueous HBr is titrated by
water?
A
C, 12.0;
 1994 UNIVERSITY OF WATERLOO
31. What mass of dry NaCl should one use to make
34. If one drop (0.05 mL) of 2.0 mol/L aqueous
hydrochloric acid is added to 1.00 L pure water,
the hydrogen ion concentration in the solution
after mixing will be
2.00 L of a 0.147 mol/L sodium ion solution?
Relative atomic masses: Na, 23.0; Cl, 35.5
A
B
117 g
C
17.2 g
D
10.4 g
E
A
1.0 x 10−2 mol/L
B
1.0 x 10−3 mol/L
C
1.0 x 10−4 mol/L
D
1.0 x 10−5 mol/L
E
1.0 x 10−6 mol/L
28.3 g
5.22 g
32. If 4.0 g of sodium hydroxide is dissolved in enough
water to make 400 mL of solution, what is the
molar concentration of the solution?
35. By addition to water, 30.0 mL of 6.00 mol/L sulfuric
acid is diluted to 150.0 mL. What is the
concentration of sulfuric acid after dilution?
Relative atomic masses:
H, 1.01; O, 16.0; Na, 23.0
A
1.20 mol/L
A
10.0 mol/L
B
1.50 mol/L
B
0.40 mol/L
C
2.40 mol/L
C
0.25 mol/L
D
3.00 mol/L
D
0.040 mol/L
E
4.80 mol/L
E
0.010 mol/L
36. AB2 is the salt of a strong acid and a strong base.
A 0.020 mol/L solution of this salt is a saturated
solution at 25°C. What is the concentration of B−
ions in solution?
33. Sodium hypochlorite is prepared by the reaction
2 NaOH + Cl2 → NaCl + NaClO + H2O
If 71 g of chlorine, Cl2, is bubbled into a solution
containing 50 g of sodium hydroxide, which
component limits the quantity of sodium
hypochlorite formed?
A
1.0 x 10−7 mol/L
B
4.0 x 10−4 mol/L
C
1.0 x 10−3 mol/L
Relative atomic masses:
H, 1.01; O, 16.0; Na, 23.0; Cl, 35.5
D
2.0 x 10−2 mol/L
E
4.0 x 10−2 mol/L
A
Cl2
B
NaCl
C
H2O
D
NaOH
E
NaClO
 1994 UNIVERSITY OF WATERLOO AVOGADRO EXAM / 7
37. Choose the one pair of salts whose aqueous
solutions would, upon mixing, create a precipitate.
39. Select the one ion or molecule that is NOT
tetrahedral
A
Na2SO4 and (NH4)2S
B
NaNO3 and MgBr2
A
NH4+
C
Ag2SO4 and KNO3
B
CH4
D
CuSO4 and CaCl2
C
SiCl4
E
(NH4)2CO3 and KNO3
D
PCl+4
E
TeCl−4
38. Which of the following is the most acidic?
40. Which quantity of lead metal has the greatest
mass?
A
Drinking water
B
Human saliva
A
22.4 mol
C
Cow's milk
B
1.0 mL
D
Human gastric juice
C
E
Seawater
D
E
207.2 g
6.0 x 1023 atoms
One formula mass expressed in grams
THE END
8 / AVOGADRO EXAM
 1994 UNIVERSITY OF WATERLOO