Atoms and Atomic Theory

1. Compare physical properties and chemicals and provide examples of each.

2. Classify each of the following as either a physical or chemical property:
a) Gasoline is a clear, pinkish solution
b) Propane burns in air
c) Water boils at 100^oC
d) Electric current can split water into hydrogen and oxygen gas

3. When a substance takes on new characteristics, i.e., shows new physical properties, what kind of change has occurred?

4. A piece of burning wood becomes carbon dioxide, water, ash and energy. This is an example of which type of change? Explain.

5. When aluminum metal is added to hydrobromic acid, hydrogen gas and aluminum bromide solution are formed.
a) What kind of change has occurred? Explain.
b) Which substances are the reactants and which are the products?

6. When sodium carbonate is added to water, the sodium carbonate dissolves. When hydrochloric acid is added to the solution, it fizzes. What kind of changes have occurred?

7. What evidence could one look for to determine if a chemical change had taken place?

8. Explain the WHMIS system and why it was developed.

9. What type of information can be learned from a MSDS?

10. Distinguish between a mixture and a compound.

11. Define the two components of a solution.

12. Provide an example of each of the following: element, compound, mixture, solution

13. Describe the role of atomic numbers, groups, and periods in organizing the elements on the periodic table.

14. Define atomic number, atomic mass, and mass number.

15. What is the purpose of the "staircase" on the periodic table?

16. Set up a chart to compare metals and nonmetals with respect to the following:
a) lustre
b) conductivity
c) location on periodic table
d) state at room temperature
e) numbers of electrons in outer orbit
f) tendency to gain or lose electrons
g) charges of ions formed
h) examples

17. Based on the periodic table, predict whether silicon would conduct electricity; be malleable; be lustrous.

18. Describe each of the atomic models that have been suggested as we developed our current one.

19. State the name, charges, and locations within the atom of the primary sub-atomic particles. Which sub-atomic particles control the atom's physical properties? Which sub-atomic particles control the atom's chemical properties?

20. Which subatomic particle occupies most of the volume of an atom? The mass?

21. Why is it that atoms are neutral in charge?

22. What is an element?

23. State the symbol, atomic number, and atomic mass of each of the following: boron, neon, magnesium, potassium, and aluminum.

24. What is an isotope?

25. Why don't atoms have atomic masses that are whole numbers?

26. How many neutrons in an atom of ¹⁷O?

27. State the number of protons, neutrons and electrons in each of the following: ⁵⁰Cr, ³⁷Cl, ²⁶Mg, ¹⁹³Ir, ²⁹Si, ²²Ne

28. Draw Bohr model diagrams of boron, chlorine, nitrogen, and beryllium.

29. a) Draw Bohr diagrams for the ions formed by each of the atoms in the previous question.
b) State the number of electrons gained or lost from each.
c) State the charge on each of the ions.
d) Name the noble gas that has the same electron arrangement for each.

30. Identify each of the following elements: 1 proton, 4 protons, 8 protons, 12 protons, 20 protons, 30 protons.

31. State the number of protons that would be in the nucleus of each of the following: uranium, selenium, helium, and curium.

32. Calculate the number of energy levels containing electrons for atoms of hydrogen, lithium, and sodium. What pattern do you notice?

33. Identify the number of energy levels which contain electrons in each of the following: P, H, Ca, F, and C.

34. What kind of arrangement of electrons in the outer orbit do stable ions have?

35. Use the periodic table to predict the number of occupied energy levels and the number of outermost electrons for each of the following: beryllium, chlorine, krypton, iodine, lead, arsenic, and cesium.

36. What is an ion?

37. a) How are positive ions formed? Negative ions?
b) "Sharing" is a characteristic of which type of bond?
c) "Transfer" is a characteristic of which type?
b) How would charges of i) 2+ ii) 3- be created?

38. What do we call a chemical bond that is an attraction between oppositely charged ions?

39. What part of the atom is involved in the formation of bonds?

40. Distinguish between covalent and ionic bonds.

41. Beryllium and fluorine react to form an ionic compound.
a) which element is the metal and which is the nonmetal?
b) Draw Bohr diagrams of beryllium and fluorine.
c) How many electrons must each gain or lose to become stable ions?
d) Draw sketches to show how this compound forms by the transfer of electrons.
e) Indicate the charges on each of the ions.
f) What is the overall charge on the compound?

42. How many electrons are found the first three orbits?