Quiz, Stoker, Chapters 5-7

1. Using a Table of Electronegativity values, what type of bonding will the following compounds have? Explain your answer.

a. O₂ b. KF
c. NO₂

2. Without using a Table of Electronegativity values, what typing of bonding will be in each of the following. Explain your answer.

a. CS₂ b. N₂ c. Ca(NO₃)₂ d. AgF

3. Without using a table of Electronegativity values, circle the element that you would expect to be more electronegative of the two listed. What does this mean to be more electronegative?

a. O or S
b. P or S

4. On scratch paper, make Lewis Electron Dot diagrams for the molecules listed. Then fill in the table indicating shape and polarity.

Formula	Shape	Polar or Nonpolar?
Br₂
CO₂
NF₃
H₂S
BBr₃
CCl₄
CH₃Br

5. Draw Lewis Electron Dot structures for the following polyatomic ions. Then list the shape of each. (Note that since these are ions they will be ionically bonded to another ion not listed in the problem. So remember you are just drawing “half” of a compound.)

a. PO₄ ^–3 b. NH₄⁺¹ c. SO₃^-2

6. Draw Lewis electron dot structures for the following diatomic molecules. Then list whether each has a single, double or triple bond between atoms.

a. N₂ b. H₂ c. O₂

7. Sketch the electron dot structure for carbonate, CO₃^-2 and sulfite SO₃^-2. For each one, list the number of bonding and non-bonding (lone pairs) electrons on the central atom. How does this affect their shapes?

8. The molecule NF₃has polar bonds and is a polar molecule whereas the molecule CF₄ also has polar bonds but is a non-polar molecule. Explain why this statement is true.

9. Name the following covalent compounds:

a. SO₂ b. N₂O
c. P₂O₅ d. SCl₆ e. CCl₄

10. Using your own words explain the significance of a “mole” and why Avogadro would have wanted to calculate it.

11. What is the formula mass of

            a. HF
            b. H₂S
            b. MgCO₃            c. Al(OH)₃

12. Complete these calculations by filling in the blanks

            a. 1 dozen books = ______ books = 24 pounds
            b. 2 dozen books = ______ books = _____ pounds
            c.   1 mole Zn = _____ atoms = _____ grams
            d. 3 moles Zn = _____ atoms = _____ grams
            e. 1 mole CO₂ = _____ molecules = _____ grams
            f.   _____ moles CO₂ = _____ molecules = 88.0 grams
            g. _____ moles CO₂ = 2.4 X 10²⁴molecules= _____ grams

13. a. How many grams are in 3 moles of He?

b. If you have 60.3 grams of Ne, how many moles and how many atoms do you have?

14. Given the balanced equation for the rusting of iron:

Fe (s) + O₂ (g) ® Fe₂O₃ (s) + E

a. State what the reaction means in words, including the meaning of each symbol listed.

b. Balance the equation

c. What is the meaning of the coefficients in letter “b”

d. List the number of grams of products and reactants involved if the
coefficients are moles.

e. Set up a ratio of the number of grams of iron that will react with oxygen.

15. Balance these equations:

a. Al + O₂ ® Al₂O₃ b. Sn + Cl₂ ® SnCl₄ c. Zn + HF ® ZnF₂ + H₂ d. Al₂S₃ + Pb(NO₃)₂ ® Al(NO₃)₃ + PbS
e. C₂H₆ + O₂ ® CO₂ + H₂O

16. What is the difference between kinetic and potential energy? Compare and contrast the KE and PE in solids, liquids and gases.

17. Maria is pushing her little sister on a swing. Explain the position of the swing where it has the most PE and the most KE.

18. Which state of matter

            a. has the greatest density?
            b. has the least amount of thermal expansion?
            c. has a definite volume but indefinite shape?
            d. has the largest compressibility?
            e. has the least amount of molecular motion

19. Explain why a gas expands when heated.

20. Compare and contrast a solid and liquid using the Kinetic theory.