These are questions from a previous year's exam.  They may not all apply to what is expected this year 2006-2007

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Part I: Multiple Choice:

1.         Which of the following gas particles would have the greatest velocity if each had the same kinetic energy?  a) bromine  b) chlorine  c) ammonia  d) hydrogen  e) argon

2.         How many significant figures does 0.00045 have?

a. one;  b. two;  c. three;  d. five;  e. six.

3.         Aluminum is an example of a class of elements known as:

            a. metals;  b. non-metals;  c. metalloids ;  d. noble gases.

4.         How many electrons can a d sublevel hold?

            a. 10;  b. 2;  c. 5;  d. 7

5.         The state in which the electron in an atom has the lowest possible energy is the

            a. ground state;   b. excited state;   c. inert state;  d. radiation-emitting state.

6.         The Bohr model of the atom:  a. was referred to as the “plum pudding atom.”   b. described a nuclear atom in which electrons surround a dense nucleus.   c. described the path of electrons as orbits around the nucleus.   d. was the quantum mechanical model.

7.         What is the charge of iron in FeSO4?

            a. +1;   b. +2;   c. +3;   d. none of the above. FeSO4 is a covalent compound.

8.         The outermost electrons of elements in groups IIIA - 0 are filling what kind of sublevel?

            a. s;   b. p ;   c. d;          d. f.

9.         How many electrons are needed to fill the 4th energy level?

            a. 18;   b. 2 ;   c. 32;   d. 40.

10.       The energy required to remove an electron from an atom in the gas phase is the

            a. ionic energy;   b. ionization energy;   c. electronegativity;   d. electron affinity.

11.       What is the correct electron configuration of phosphorus?

            a. 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p3

            b. [Ar] 4s2 3d10 4p3

            c. both a and b are correct

            d. neither a nor b is correct

12.       What is the correct orbital diagram for nitrogen?

            a.                       b.                       c.                       d.

13.       Which statement about the periodic table is FALSE.

            a. Elements of the same chemical families have similar properties.

            b. The periodic table is arranged according to increasing atomic number.

            c. Elements of the same period have similar chemical and physical properties.

            d. The periodic table is arranged according to increasing number of protons.

14.       Which one of the following sets of elements contains an element that is NOT in the same family as the others?

                   a. tin, lead, carbon

                   b. oxygen, carbon, nitrogen

                   c. argon, krypton, helium

                   d. fluorine, chlorine, iodine

15.       As one proceeds from sodium to chlorine in the Periodic Table

                   a. the atomic radius increases while the electronegativity decreases

                   b. the atomic radius decreases while the electronegativity increases

                   c. the atomic radius and the electronegativity both decrease.

                   d. the atomic radius and the electronegativity both increase.

16.       The periodic law states that the physical and chemical properties of the elements are periodic functions of their:

            a. wavelengths;   b. combining weights;   c. atomic weights;   d. atomic numbers.

17.       The mass of 6.02 x 1023 molecules of chlorine gas is:

            a. 1.00 g;   b. 35.5 g;   c. 71.0 g;   d. 6.022 x 1023 g.

18.       What is the percent composition of nitrogen in the compound (NH4)2S?

            a. 21%;   b. 36%;   c. 41%;   d. 0.36%;   e. 0.41%.

19.       What is the proper name of CuSO4?

            a. Copper (I) sulfate;   b. Copper (II) sulfate;   c. Copper sulfur tetroxide;   d. Copper (II) sulfide.

20.       What is the correct formula of iron (III) phosphate?

            a. FePO3

            b. FePO4

            c. Fe3(PO3)3

            d. Fe2(PO4)3

21.       The polyatomic ion, NH4+, is called:

            a. nitrate;   b. ammonia;   c. ammonium;   d. nitride.

22.       What is the molecular formula of a compound which has an empirical formula of CH2O and has a molecular mass of 180.00 g.

            a. CH2O;   b. C2H4O2;   c. C5H10O5;   d. C6H12O6

23.  .....Al2(C2O4)3(s) ---->......Al2O3(s) + ......CO(g) + ......CO2(g)

                  According to the equation for the reaction represented above, what is the mole ratio of CO to             CO2 that is produced by the decomposition of aluminum oxalate (Al2(C2O4)3)?

                                    a.  1 mole CO: 1 mole CO2

b.  1 mole CO: 2 moles CO2

                        c.  1 mole CO: 3 moles CO2

                        d.  2 moles CO: 1 mole CO2

24.  ......LiAlH4(s) + ......BCl3(l) ----->......B2H6 + ......LiCl(s) + ......AlCl3(s)

When the equation for the reaction represented above is balanced and all coefficients are reduced to the lowest whole number terms, the coefficient of B2H6 is:  a.1;   b.2;   c.3;   d.4;   e.6.

25.                   2Al(s) + Fe2O3 --> Al2O3 + 2Fe(s)

   According to the equation for the reaction represented above which of the following statements is true.

            a. If 2 moles of Al is used, 1 mole of Fe is produced.

            b. If 1 mole of Al is used, 0.5 mole of Fe2O3 is consumed.

            c. If one mole of Al is used, 1 mole of Al2O3 is produced.

            d. If 0.5 mole of Al is used, 1mole of Al2O3 is produced.

            e. If 0.5 mole of Al is used, 0.5 mole of Fe2O3 is consumed.

26.       Which of the following combinations of particles represents an ion net charge of -1 and of a mass    number 80

a. 44 neutrons, 35 protons, 36 electrons

b. 44 neutrons, 36 protons, 35 electrons

c. 44 neutrons, 36 protons, 36 electrons

d. 45 neutrons, 35 protons, 35 electrons

e. 45 neutrons, 35 protons, 36 electrons

27. C2H4(g) + 3O2(g) ----> 2CO2(g) + 2H2O(l)

When 100.0 grams of O2 are allowed to react completely with 1.00 mole of C2H4 according to the equation above, which of the following results?

                        a. Some C2H4 remains unreacted.

                        b. Some O2 remains unreacted.

                        c. Only CO2 and H2O are present when the reaction has run to completion.

                        d. Less than 2 moles of CO2 is formed.

                        e. The partial pressure of O2 falls to zero.

28.  .....Ag+(aq) + ......S2-(aq) ----> ........(s)

When the equation for the reaction represented above is completed and balanced by the use of lowest whole number coefficients, the coefficient for Ag+ is: a.1;   b.2;   c.3;   d.4;   e.6.

29.             According to quantum mechanics, correct statements concerning the electron in the hydrogen atom include which of the following?

                        I.It moves in a definite circular orbit around the nucleus.

                        II. It is associated with definite energy levels.

                        III. It occupies a fixed position in space with reference to the nucleus.

a. I only

b. II only

c. I and III only

d. II and III only

e. I, II, and III

30.       When the external pressure is 505 kPa, what is the vapor pressure of water at its boiling point?   a) 0 kPa  b) 101 kPa  c) 505 kPa  d) 1010 kPa  e) not enough information

31.       How many kilocalories of heat are required to raise the temperature of 225 g of aluminum from 20oC to 100oC? (specific heat of aluminum = 0.21 cal/(g xoC))

a)     0.59 kcal  b) 3.8 kcal  c) 85 kcal  d) None of the above

32.       For a particular compound, which of the following pairs can represent the empirical and the molecular formula, respectively?

a. CH3 and C3H6;  b. CH2 and C2H2;  c. CH2 and C3H9;  d. CH and C6H6;  e. CH and CH4

33.       H2O(l) --> H2O(g)

Correct statements concerning the process above occurring at 100o C include which of the following?

I.  The vaporization process is endothermic.

II. The system is absorbing heat.

III. The average potential energy of the vapor molecules is greater than that of the liquid molecules.

a. I only;   b. II only;   c. I and III only;   d. II and III only;   e. I, II, and III.

34.       Which of the following statements about the halogens (X) is true?

a. They all form X- ions.

b. They have the lowest ionization (potential) energies of the elements in their respective periods.

c. The are all solids.

d. They have the largest atomic radii of their period.

e. They occur as single atoms in their elemental form.

Diagram for # 35

35.       Both of the gas samples represented above are at the same temperature and pressure. The mass of H2 in the 1 liter container is 0.20 gram. The mass of X in the two liter container is 8.0 grams. The molecular weight of X is:  a.10;   b.20;   c.40;   d.60;   e.80.

36.       At 23oC, 200 milliliters of an ideal gas exerts a pressure of 750 mm of Hg. The volume of the gas at 0oC and 760 mm of Hg found from which of the following expressions?

a.  200 x (760/750) x (273/296) ml

b.  200 x (750/760) x (0/23) ml

c.  200 x (760/750) x (23/0) ml

d.  200 x (760/750) x (296/273) ml

e.  200 x (750/760) x (273/296) ml

Table for #37:

37.       The ionization energies (potentials) for the removal of different electrons from an atom of an element in the gas phase are shown above. An atom of this element is most likely to form an ion that has the charge of:  a. +1;   b. +2;   c. +3;   d. +4;   e. +5.

38.       Of the following ground state electron configurations, the one that represents the element of lowest first ionization energy (potential) is:

a.1s22s22p5

b.1s22s22p6

c.1s22s22p63s1

d.1s22s22p63s2

e.1s22s22p63s23p1

39.       A 250 gram sample of a hydrated salt was heated at 110o C until all water was driven off. The             remaining solid weighed 160 grams. From these data, the percent of water by weight in the             original sample can be correctly calculated as:

a. (160/340) x 100

b. (90/340) x 340

c. (160/250) x 100

d. (90/250) x 100

e. (90/160) x 100

42.       A compound composed of three different types of elements is:

  a. table salt;   b. water;   c. potassium perchlorate;   d. carbon dioxide.

43.       Which of the following formulas does NOT represent a molecule?

  a. NH3;   b. H2O;   c. NaCl;   d. CO2.

44.       The formula for dinitrogen tetrafluoride would be:  a. NF;   b. N2F;   c. N2F3;   d. N2F4.

47.       What is the volume occupied by 71.0 g of chlorine gas at STP?

            a)   22.4 L  b)   44.8 L  c)   56.0 L  d)   67.2 L  e)   78.4 L

48.       What is the number of moles of gas in 56.0 L of oxygen at STP?

            a)   0.50 mol            b)   1.00 mol            c)   1.5 mol      d)   2.00 mol            e)   2.50 mol

49.            Compared with 1 mole of chlorine gas at STP, 1 mole of hydrogen gas at STP occupies:  a) more volume.  b) less volume.  c) the same volume.

Part II: Matching: (1 point each) Match the letter of the correct definition or example with the

numbered vocabulary.  some letters will not be used.  There is only one appropriate answer for each number.  Place your answer on the scantron sheet starting with number 68.

68.       isotope                          a.  his experiments led to the discovery of the electron.

69.            allotrope                      b.  his experiments led to the discovery of the nucleus.

70.       atomic number             c.  the number of atoms found in 12.0 grams of carbon-12

71.            Rutherford                   d.  is a cute brown furry thing that lives in the ground

72.       mass number             e.  carbon-14 and carbon-12 are examples

73.       Charles                         ab.  graphite and diamond are examples.

74.       atomic mass                 ac.  H2, N2 and O2 are examples.

75.       Hund’s Rule                 ad.  developed a gas law relating pressure and temperature

76.       Boyle                            ae.  the ability to attract and acquire electrons; this process releases energy

77.            Avogadro’s number            bc.  ability of an atom to attract electrons when bonded to another atom

78.       Pauli Exclusion Princ.            bd.  developed a gas law relating pressure and volume

79.       Dalton                          be.  developed a gas law relating volume and temperature

80.            electronegativity            cd.  developed a gas law relating moles and pressure

81.            transition elements            ce.  orbitals of the same energy level will contain one electron each with the

 same spin until they have to contain two

82.       Gay-Lussac              de.  This number is in common with all isotopes of the same element.

                                                abc.  This number indicates the number of protons and neutrons in an atom.

                                                abd.  relative, weighted average of all known types of atoms of the element

                                                abe.  developed a relationship between rates of effusion and molar masses

                                                acd.  copper, silver and gold are examples of these

                                                ace.  Most actinides fall in this category.

                                                ade.  provided the first principles of the modern atomic theory

                                                bcd.  No two electrons can have the same four quantum numbers in the

same atom.

Part II: Problems and Short Answers:

Answer the following problems in  the space given.  BE SURE TO SHOW YOUR WORK FOR FULL CREDIT.  For each question answer all the parts of the question in complete sentences.

1. Determine the empirical formula of a certain copper sulfide ore if a sample of the compound contains 79.8% by mass of copper (Cu).

2.  Write balanced equations for each of the following:

            a.  the formation of crystalline mercury (I) oxide from the elements.  (Mercury is Hg)

            b.  the combustion of ethane gas (C2H6)

            c.              Al(s)  +              CuCl2(aq)  à

d.              Fe2O3(s)  à

8.            Explain the relationship between the periodic trends, ionization energy and atomic size in terms of the fundamental forces of the atom.

 13.            Discuss Rutherford’s experiment regarding the structure of the atom.  What did he discover about the atom’s structure?  How did he come to this conclusion?  What question remained to be answered by his student, Neils Bohr?

 Extra Credit:            Balance the following equation. 

            NaI +               MnO2 +          H2SO4 à        Na2SO4 +          MnSO4 +          H2O +              I2

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