Chem Mystery Make-up

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Measurement/Units

1. State whether the following basketball free-throw shooters are accurate, precise, both or neither.

      1. 99 of 100 shots are made.
      2. 99 of 100 shots hit the front of the rim and bounce off.
      3. 33 of 100 shots are made; the rest either miss the rim completely or rebound off the backboard.
  1. Three students made multiple weighings of a copper cylinder, each using a different balance. The correct mass of the cylinder had been previously determined to be 47.432 g. State whether the students were accurate, precise, both or neither.
    2.

    Mass of cylinder (g)

     

    Jim

    Lee

    Bob

    Weighing 1

    47.13

    47.45

    47.95

    Weighing 2

    47.94

    47.39

    47.91

    Weighing 3

    46.83

    47.42

    47.89

    Weighing 4

    47.47

    47.41

    47.93

     

  2. Round off each of the answers correctly.
      1. 8.7 g + 15.43 g + 19 g = 43.13 g
      2. 4.32 cm X 1.7 cm = 7.344 cm2
      3. 853.2 L - 627.443 L = 225.757 L
      4. 38.742 Kg ¸ 0.421 = 92.02375 Kg
      5. 5.40 m X 3.21 m X 1.871 m = 32.431914 m3
      6. 5.47 m3 + 11 m3 + 87.300 m3 = 103.770 m3
  1. Include the measurements taken from the page of notes for the balance, ruler, and graduated cylinder. Click here
  2. List the SI base unit of measurement for these quantities.
      1. time
      2. length
      3. temperature
      4. mass
  1. A weather balloon is inflated to a volume of 2.2 X 103 L with 37.4 g of helium. What is the density of helium in grams per liter?
  2. Does the density of an object depend upon its size? Explain.
  3. Calculate the experimental percentage error for the following.
      1. Jim's weighing 1 in problem #2.
      2. Lee's weighing 3 in problem #2.
      3. Bob's weighing 4 in problem #2.

 

Kinetic Theory of Matter

  1. How can you raise the average kinetic energy of the water molecules in a glass of water?
  2. What is significant about the temperature absolute zero?
  3. State the four principles of the kinetic theory of matter.
  4. Describe Brownian motion in your own words.
  5. If a bottle of perfume was opened in a closed room, the smell would eventually reach all parts of the room. What do we call this phenomenon?

 

Scientific Method/Experimental Design

  1. What is the purpose of an experiment as part of the scientific method?
  2. Distinguish between a problem, hypothesis, and a conclusion.
  3. At what point in the scientific method do we use the experimental design.
  4. List 5 components that an experimental design must have.

5. Complete scenarios 2 - 5 from the notes. Click here