1. How many significant figures are in each of the following measurements: (.2 each)

a. 200.010 cm     b. 8.0 E 2 mL c. 170 g. d. .0010000 mL

2. Solve each of the following problems: (.2 each)

a. 83.2 cm + 6.12 cm b. 4.1 g – 4.07 g          c. 105.735g + .3 g
d. (9.1 cm)(1. cm)        e. (4.102 cm)(3.21cm) f. 9 g/ .0123 mL

3. EXPLAIN why the following are wrong or inaccurate measurements. Then give the probable correct measurements. You may look at the laboratory instruments for this.

a. 1.32517 cm from a laboratory ruler
b. 5.000 mL from a 1 mL 1-line pipet
c. 1. mL from a 100 mL graduated cylinder
d. 100 mL from a 250 mL Erlenmeyer flask
e. 1.0E2 mL from a 100 mL volumetric flask

4. The following data was collected for an experiment with the buret:

mass of flask: 21.45 g;
initial volume reading: 10.09 mL;
final volume reading: 21.42 mL;
mass of flask + water: 31.67 g

Calculate

a. the mass of water
b. the volume of water
c. the density of water
d. the per cent error (if the correct density is .993 g/mL)

5. a. A cube of side length 8.00 cm has a mass of 200 g. What is its density?
5. b. What is the volume of 82.2 g of .786 g/mL liquid?

6. How could you show, from density lab results, that density is an intensive property. How would a results table indicate that? How would a graph illustrate that?

7. How many decimal places should one get using the following 10 mL pipet?

Explain your reasoning.

8. What sample size would you aim for in order to get the best value for the density of water using a 50 mL burette? Explain why you believe your answer and what evidence you have to support it.

9. A number used as a measurement has two properties- size and uncertainty. From the following measurements: .004000 g, .40 g, .40 g, 4 g, 4.0 g, 4.0000 g, 40 g, 400000 g

(a) select three of about the same size but different degrees of uncertainty and
(b) three of about the same degree of uncertainty but different sizes.

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