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ISLAMIC UNIVERSITY – GAZA
General
Chemistry "A"
FACULTY OF SCIENCE
Final Exam
Spring Semester, 2008
Date: 19/05/2008
------------------------------------------------------------------------------------------------------Student Name : _____________________
ID Number
: _____________________
Part A. True or False
Time : 2 hrs
70
(10 marks)
1. (
) Mole can be defined as the Avogadro's number of particles of any substance
or the amount of substance in one molar mass.
2. (
) In a many-electron atom the energies of the Px, Py and Pz orbitals are the
same.
3. (
) An electrolyte is a substance that, when dissolved in water, results in a
solution that can conduct electricity.
4. (
) Molarity (M), or Molar Concentration is defined as the number of moles of
solute in 1 liter (L) of solution
5. (
) Isolated system which does not allow the transfer of either mass or energy.
6. (
) Process in which heat is absorbed by the surroundings from the system is
called exothermic process.
7. (
) The formula AlCl3 indicates one mole of aluminum chloride contains one
mole of aluminum atoms and three moles of chloride atoms.
8. (
) According to the Pauli Exclusion Principle, no two electrons in an atom can
have the same four quantum numbers.
.
9. (
10. (
) Electronegativity is a measure of the tendency of an atom to attract the
bonding electrons in a chemical bond toward itself
) According to the rules of assigning oxidation numbers, free elements
(uncombined state) have an oxidation number of zero.
Part B. Choose the Correct Answer
(24 marks)
1. The reaction between an acid and base is called:
1
A. Displacement reaction `
B. Addition reaction
C. Precipitation reaction
D. Neutralization reaction
2. All of the following are true about the information conveyed by the chemical
formula N2O4 for the compound dinitrogen tetroxide except:
A. The mass of one molecule of N2O4 is 92 amu.
B. The mass of one mole of N2O4 is 92 grams.
C. There are six atoms in a molecule of N2O4.
D. NO2 would be a better way to write the molecular formula.
3. Mixing which of the following will produce a precipitation reaction?
A. HNO3(aq) and Sr(OH)2(aq)
B. NaOH(aq) and KBr(aq)
C. Zn and HCl(aq)
D. NaSO4(aq) and Ba(OH)2(aq)
4. Which of the following elements has the greatest electronegativity?
A. F
B. I
C. Li
D. Cs
5. The element with the largest atomic radius is located in which part of the
periodic table?
A. Upper left
B. Upper right
C. Lower left
D. Lower right
6. The Tendency of a bonded atom to attract the shared electron pairs toward
itself is indicated by its:
A. Electronegativity
B. Ionization energy
C. Valence electrons
D. None of the above
7. In diprotic acid; each unit of the acid gives up _______ in two separate steps:
A. Two hydrogen molecules
B. Two hydrogen ions
C. Three hydrogen ions
D. Two electrons
8. For displacement reactions involving halogens the reactivity is:
A. Br2 > Cl2 > F2 > I2
B. Cl2 > F2 > Br2 > I2
C. F2 > I2 > Br2 > Cl2
D. F2 > Cl2 > Br2 > I2
9. Under the (STP) conditions 1 atm and 0 oC, one mole of an ideal gas occupies:
A. 22.4 L
B. 22.4 ml
C. 224 L
D. 2.24 L
10. The spectator ions in the following reaction are:
Pb(NO3)2 (aq) + NaI (aq)  PbI (s) + NaNO3 (aq)
A. Pb2+ and I-
B. Pb2+ and NO3- C. Na+ and NO3-
2
D. Na+ and I-
11. According to the solubility rules, which of the following compounds is soluble
in water?
A. AgBr
B. Ba(OH)2
C. CaCO3
D. ZnS
Part C. Solve and Choose the Correct Answer
(36 marks)
You must show your solution steps:
1. 3.01 x 1023 molecules of CO2 have a mass of:
A. 22.0 g
B. 44.0 g
C. 30.1 g
D. 3.0 g
2. The oxidation number of Cr in dichromate ion, Cr2O7-2, is:
A. +5
B. +6
C. +7
D. +8
3. If a sample of nitrogen occupies a volume of 4.0 liters at 0 0C, what
volume will it occupy at 80 0C if the pressure remains constant?
A. 5.17 L
B. 4.0 L
C. 32.0 L
D. 8.02
4. A compound has an elemental analysis of 49.08 % Mn and 50.92 % F.
what is the empirical formula of the compound?
A. MnF
B. Mn2F
C. MnF2
D. MnF3
5. The molarity of a solution containing 3.54 g of NaCl in 500ml of solution
is:
A. 0.0303 M
B. 0.0606 M
C. 0.121M
D. 1.77 M
6. Calculate the mass of excess reagent remaining at the end of the reaction
in which 90 g of SO2 are mixed with 100 g of O2. 2SO2 + O2  2SO3
A. 11.5 g
B. 22.5 g
C. 67.5 g
D. 77.5 g
7. Which one of the following gases will have the greatest density at STP?
3
A. H2
B. CH4
C. Cl2
D. Ar
8. The maximum number of electrons in the energy level with n = 4 is:
A. 4
B. 16
C. 32
D. 50
9. What is the wavelength in meters of a proton (mass = 1amu) traveling at
1/1000 of the speed of light? (c =3.00 x 108 ms-1)
A. 1.33 x 10-12
B. 1.33 x 10-15
C. 2.21 x 10-39
D. 3.67x10-63
10. Which is the correct electronic configuration for zirconium (Zr)?
A. [Kr] 4d25s2
B. [Kr] 4d35s2
C. [Ar] 4d25s2
D. [Kr] 4d26s2
11. The atmosphere of Mars is mostly CO2, at a pressure of 5.5 mmHg at a
temperature of - 31.4 oC. What is the density of the atmosphere?
A. 0.120 g/L
B. 0.055 g/L
C. 0.016 g/L
D. 0.116 g/L
12. How many O2 molecules occupy a 1.0 L flask at 75oC and 777 mmHg?
A. 3.14x1018
B. 2.11x1015
C. 1.02x1011
D. 2.16x1022
13. How many grams of NaCl are present in 45.0 ml of 1.25 M NaCl?
A. 3.29 g
B. 4.50 g
C. 1.25 g
4
D. 2.5 g
 Good Luck 
Mr. Ibrahim Lubbad
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