1. Unit 2 Review

2.  TRUE or FALSE Salt (NaCl) is a pure substance and an element.

3. ANSWER  False… pure substance and compound. Two elements combined = compound Two elements combined = compound

4.  Which state of matter would take the shape of it’s container and has a fixed/definite volume?

5. ANSWER  Liquid

6.  A popsicle melting on the sidewalk is an example of what type of change?

7. ANSWER  Physical…all phase changes (solid  liquid  gas) are physical changes.

8.  “A shiny piece of steel rusted from sitting out in the rain.”  Which part of this statement represents a physical property? Which part represents a chemical property?

9. ANSWER  “A shiny piece of steel rusted from sitting out in the rain.”  “SHINY” is physical, describing what it looks like  “RUSTING” is chemical, because rust has a different composition than steel.

10.  Matter changing from its liquid state to its gaseous state is called ______.

11. ANSWER  Vaporization Boiling Boiling Evaporation Evaporation

12.  What is an ion?

13. ANSWER  An atom with a positive or negative charge.  An atom that has lost or gained electrons.

14.  If at ion has a positive charge, did it GAIN electrons or LOSE electrons?

15. ANSWER  LOSE electrons so that the there are now more positive protons than there are negative electrons.

16.  What charge would group 7 most likely have?

17. ANSWER  -1

18.  What charge would group 2 most likely have?

19. ANSWER  +2

20.  How many neutrons does Carbon-14 have?

21. ANSWER  14 is the mass number of that particular isotope of Carbon and the atomic number of Carbon is 6, so 14-6= 8 neutrons.

22.  TRUE or FALSE To get an isotope, you fluctuate the number of electrons.

23. ANSWER  FALSE. You would fluctuate the number of neutrons to change the mass.

24.  Who discovered protons and how? FIRST AND LAST NAME, BE DETAILED.

25. ANSWER  Ernest Rutherford by shooting alpha particles (positive particles) at a piece of foil. The alpha particles deflected, which showed they were hitting something else that was positive (protons).

26.  Who came up with the first atomic theory? FIRST AND LAST NAME.

27. ANSWER  John Dalton

28.  Who discovered electrons and how? FIRST AND LAST NAME. BE DETAILED.

29. ANSWER  JJ Thomson- cathode ray tube showed electrons are emitted. Negative side of magnet repelled (or positive side attracted) so proved they were negative.

30.  What part of the atom gives it it’s identity?

31. ANSWER  Protons

32.  Would spaghetti be a pure substance or a mixture?

33. ANSWER  Mixture (heterogeneous)

34.  What are the 3 particles of the atom and their respective charges?

35. ANSWER  Proton +  Neutron (neutral)  Electron -

36.  Why isn’t the mass of strontium-52 on the periodic table reported as 52?

37. ANSWER  The periodic table shows average atomic masses of all isotopes present

38.  How many electrons fit on energy level 1, 2,& 3?

39. ANSWER  1 st holds 2  2 nd holds 8  3 rd holds 8

40.  Who created the atom model where electrons are found on energy levels?

41. ANSWER  Niels Bohr

42.  Draw the Bohr diagram for phosphorus.

43. ANSWER  15 P  16 N  15 E

44.  Write the following info in isotopic notation Protons- 26 Protons- 26 Neutrons- 31 Neutrons- 31 Electrons- 23 Electrons- 23

45. ANSWER  57 Fe 3+ 26

46.  Atomic Number  Mass Number  Neutrons  Electrons

47. ANSWER  Atomic Number- 16  Mass Number- 33  Neutrons- 17  Electrons -18

48.  Who discovered the neutron? FIRST AND LAST NAME.

49. ANSWER  James Chadwick

50.  Protons-20  Electrons-20  Neutrons-22  Isotope name?

51. ANSWER  Calcium-42

52.  Protons-20  Electrons-20  Neutrons-22  Give the correct notation.

53. ANSWER

54.  What is the name of the element if the only information you have is there are 35 protons?

55. ANSWER  Bromine

56.  List techniques for physically separating a mixture (think about our lab)

57. ANSWER  Filtering  Using a magnet  Boiling  Dissolving