First Semester General Review for Exam                            January 2008

Unit 1: Matter and Change

Ø      Be able to differentiate elements, compounds and mixtures from names, formulas and descriptions.

Ø      State the difference between precision and accuracy.

Ø      Describe a couple of simple separation techniques to separate mixtures, i.e. salt water, sawdust and sand, chalk dust and powdered sugar,

Unit 2: Atomic Structure

Ø      Summarize Dalton’s, Thomson’s, Rutherford’s, Bohr’s, and Schrodinger’s contributions to the development of the current atomic theory.  State a key thought or experiment and the resulting atomic model.

Ø      Review the composition of the atom and how it is described and the number of each component is determined.

Ø      Review nuclear reactions and be able to write these reactions for alpha and beta decay.

Ø      Discuss electron arrangement in the electron cloud in terms of:

§         Orbital capacity, shapes and relative energies

§         Rules for filling the electron cloud with electrons

§         Electron configurations

§         Orbital diagrams

SAMPLE QUESTIONS from UNIT TEST 2:

Column A                                            Column B

1.  Dalton                                 a.  Originally coined the term “atomos”

2.  Rutherford                           b.  Stated that electrons have fixed orbits in an atom

3.  Thomson                             c.  Says only two electrons per orbital

4.  Schrodinger                         d.  Says that spreading out electrons into equal energy orbitals gives a lower energy electron arrangement

5.  Bohr                                    e.  Introduced the “Modern Atomic Theory”

6.  Heisenberg                          ab.  Proposed the “Nuclear Model” of the atom

7.  Aufbau                                ac.  Proposed the “Uncertainty Principle”

8.  Pauli                                    ad.  Tells chemists about the orbital filling order for electrons

9.  Hund                                   ae.  Proposed the “Plum Pudding” or “cookie dough”  atomic model

10. Democritus                         bc.  Was main author of our current “Quantum Mechanical” atomic model

Part 2:  Multiple Choice.

11. The number of neutrons in the nucleus of an atom can be calculated by: (a) adding together the numbers of electrons and protons.  (b) subtracting the number of protons from the number of electrons.  (c) subtracting the atomic number from the mass number.  (d) adding the mass number to the number of protons.

12. The maximum number of electrons that can occupy the third principal energy level is:  (a) 2. 
(b) 6.  (c) 8.  (d) 18.

13. All atoms of the same element have the same:  (a) atomic number.  (b) number of neutrons. 
(c) mass number.  (d) atomic mass.

14. Which of the following sublevels will fill first with electrons according to the Aufbau Principle?  (a) 3p  (b) 3d  (c) 4s  (d) 3s

15. The ground state electron configuration for the outermost energy level in Na is:
(a) 3s².  (b) 4s¹.  (c) 2s¹.  (d) 3s¹.

16. According to Hund’s rule, when electrons occupy orbitals of equal energy, one electron enters each orbit until:  (a) all the orbitals contain one electron, with spins parallel.  (b) all the orbitals contain one electron, with opposite spins.  (c) there are two electrons in each orbital.  (d) electron velocities become constant.

17. What is the maximum number of electrons allowed in a 3p orbital?  (a) 2,  (b) 6,  (c) 10,  (d) 18.

18. If Z is the symbol for an unknown element, which pair among the following represents isotopes of the same element?  (a) ⁵¹Z and ⁵¹Z   (b) ⁵¹Z and ⁵⁰Z  
(c) ⁵⁰Z and ⁵⁰Z²⁺  (d) ⁵¹Z and ⁵⁰Z²⁺

19. The fourth principal energy level has a total of:  (a) 4 orbitals,  (b) 16 orbitals,
(c) 32 orbitals,  (d) 9 orbital

20. In order to occupy the same orbital, two electrons must have:  (a) the same direction of spin. 
(b) low energy.  (c) opposite charge.  (d) opposite spin.

For other unit 2 questions consult your old test.

Unit 3: Periodic Table and Elements

Ø      Know the basic regions and organization of the periodic table.  Know the special names of blocks and families

Ø      Define and describe the five key periodic trends: atomic size (radius), ionic size, ionization energies, electron affinity, electronegativity.  Explain their trends in terms of fundamental forces among the subatomic particles in the atom.

SAMPLE QUESTIONS from QUIZ Ch. 6

1.      Atomic Size: (a) generally decreases from left to right across a period.  (b) is measured from the nucleus to the edge of the electron cloud.  (c) generally decreases as you move down a group.  (d) is generally less for metals than for non-metals.

2.      The element Ruthenium, Ru, is a:  (a) period 5 alkali metal.  (b) period 5 transition metal.  (c) period 5 representative element.  (d) period 4 inner transition metal.

3.      Which of the following atoms would you expect to have the largest electronegativity?  (a) Cl  (b) Br  (c) Ca  (d) Rb

4.      The representative elements do not include:  (a) Fe.  (b) C.  (c) Sr.  (d) Br.

5.      The element that contains electrons in an f sublevel is: 
(a) Sn.  (b) Eu.  (c) Zr.  (d) Cs.

6.      The smallest particle from among the following is:  (a) Mg  (b) Mg²⁺  (c) Cl  (d) Cl^1-

7.      Identify the semi-metal among the following:  (a) C.  (b) Si.  (c) Al.  (d) Zn.

Part 2:  Short Answers and Questions: 

8.      Give the name of the group of elements whose group number(s) are the following:

a)      Group 17, 7A               (b) Group IA, 1                        (c) Group IIA, 2            

9.      The outermost energy level configurations for the theoretical elements A-E are listed below.  Use the symbols A through E to answer each of the questions that follow.  You may use any of these more than once.  Give only one answer per description.

A = 3s²            B = 3s¹                      C = 2s² 2p⁶          D = 2s² 2p⁵        E = 2s² 2p⁴

      a)      Which has the smallest sized atoms?

b)      Which is an alkaline earth metal?

c)      Which has the largest electronegativity?

d)      Which has the largest sized ion?

10.  (1)Define ionization energy.  (2)State the periodic the trend in ionization energy. 
(3) Explain this trend in terms of the fundamental forces in an atom and the atomic radius.