Lab 2

Measurements: Accuracy and Precision A. Data Tables (36 points)

Place your completed data tables into your report here:

Data Table 1

Measurement

Data

Length of aluminum plastic packet 5 cm

Height of aluminum plastic packet 6.5 cm

Temperature of faucet water 23°C

Temperature of ice water 11°C

Volume of water in 10-mL graduated cylinder 10 ML

Volume of water in 50-mL graduated cylinder 10 ML Data Table 2

Measurement

Data

Inside diameter of 50-mL graduated cylinder 2.5 cm

Height of 50-mL graduated cylinder 9.5 cm

Water temperature 22°C

Initial volume of water in 50-mL graduated cylinder

10.0 mL

Mass of water in the 50-mL graduated cylinder (remember, 1 g of water weights 1 mL since its density is 1 g/mL) 10 g

Volume of water and aluminum shot in 50-mL graduated cylinder 17.5 mL

Mass of aluminum shot (given on outside of packet) 19.92 g

B. Follow-Up Questions (Show all calculations)

Part I (Each question is worth 10 points.)

1. Convert the length and height measurements for the packet that contains the aluminum shot from units of cm to units of mm using the unit-factor method.

- L= 5 cm = 50 mm

- W= 6.5 cm = 65 mm

2. Convert the temperature measurements for the faucet water and the ice water from oC to oF, using the following equation: oF = 1.8(oC) + 32.

- Faucet Water = 73.4°F

- Ice Water = 51.8°F

3. Convert the volumes of the water in the 10-mL and 50-mL graduated cylinders from mL to L, using the unit-factor method.

- 10 mL water, 10 mL = .01 L

- 50 mL water, 10 mL = .01 L

4. Looking at your measurements for the volumes of water in the 10-mL and 50-mL graduated cylinders, are your values identical? Discuss at least two reasons why the measurements were not identical.

- Mine were identical because I figured they were supposed to be and let the pipette fill completely. They would have not been identical though if you had not allowed the pipette to fill the same amount each time or if you did not fill it all the way each time.

Part