CHM 1045
Dr. Michael Blaber

Name_________________________

SS #__________________________

1. Are the following mixtures or pure substances? If they are mixtures, are they homogenous or heterogenous? (2 points total)

1. A chocolate chip cookie Heterogeneous mix
2. Yogurt (the kind with fruit on the bottom) Heterogeneous mix
3. Bottled water PURE
4. A lead fishing sinker PURE

1. You spill some sugar in a sandbox. You scoop it up as best you can, but now you have a mixture of sand and sugar. How could you separate the two? (2 points total)

You could add some hot water to dissolve the sugar. You could filter out the sand/sugar solution. (You could go on to evaporate the water to yield solid sugar again)

2. Something simple, like a candle burning, involves the following various steps which occur at the burning wick: a) the wax is heated and melts. b) The melted wax is heated further and emits flammable vapor. c) the vapors are combined with oxygen in the air and ignite to produce heat, light and soot. d) the soot may collect around the wick, making it black in color. Which of these involve chemical processes and which involve physical processes? (2 points total)

a. Physical process

b. Physical process

c. Chemical process

d. Physical process

3. If the charge of an electron was actually twice the value found by Millikan, and the charge-to-mass ratio was twice the value found by Thompson, what would be the mass of an electron? (2 points total)

Mass = charge/(charge/mass ratio) = x/y

New Mass = 2x/2y = x/y (i.e. mass identical to value found by Millikan)

4. For the "electron" in question 4, how would it behave in comparison to the b- rays in an electric field type of experiment? (2 points total)