PURPOSE:

a. To measure the masses and volumes of solids and liquids b. To calculate the densities of solids and liquids

c. To calculate the specific gravities of solids and liquids d. To calculate the volume of a rectangular object and to express the volume in volume metric units e. To record data and calculate the values in the correct number of significant figures MATERIALS:

10 mL graduatebalancetest tube rackunknown liquid

50 mL graduatetest tube100 mL beakerassorted solid objects Dropper pipettemeter stick

PROCEDURE:

Part A. Density of Water

1. Measure the mass of a 100 mL beaker to the nearest .01 g. The beaker should be dry. 2. Measure, as accurately as possible, 50.0 mL of water. Use the graduated cylinder (the bottom of the meniscus must be on the 50 mL mark. You may want to use the dropping pipette to add the last few drops of water to get exactly 50.0 mL). Add this measured volume of water to the 100 mL beaker. 3. Measure the mass of the beaker and the water. Record all measured values in the data chart for Part A of the observation section of your lab report.

All of the data charts should have two columns, one for the item measured and one for the value. The data chart for Part A should contain the following information: (*refers to calculated or theoretical values) A. Mass of the empty beaker D. *Mass of the water G. *Percent Error B. Volume of the water E. *Density of water (experimental) C. Mass of the beaker and water F. *Density of water (theoretical) Part B. Density of an Unknown Liquid

1. Measure the mass of a 10 mL graduated cylinder.

2. Fill the graduated cylinder close to the 9 mL mark with the unknown liquid. Read the volume to the nearest 0.1 mL or 0.2 mL according to the precision of the graduate. 3. Measure the mass of the cylinder and its contents carefully. Record all measured values in the data chart for Part B in the observations section of your lab report. 4. Return the unknown liquid to a container designated by your teacher. Do not return it to the reagent bottle!

The data chart for Part B should contain the following information: (* refers to calculated or theoretical values) A. Mass of the empty graduated cylinder E. *Density of unknown liquid (experimental) B. Volume of the unknown liquid F. *Specific gravity of unknown (experimental) C. Mass of the liquid and graduated cylinder G. *Specific gravity of unknown (theoretical) D. *Mass of unknown liquid H. *Percent error for specific gravity Part C. Density of a Solid

1. Obtain a solid object from your instructor and measure its mass to the nearest .01 g. 2. Fill a 50 mL graduated cylinder close to the 25 mL mark. Record the volume of water to the nearest .1 mL. 3. Tilt the graduated cylinder carefully and slip the solid object down the inside of the cylinder into the water. Be cautious. Do not allow any of the water to splash out of the cylinder and do not drop the object because you may break the cylinder! Record the new volume of the contents of the graduated cylinder to the nearest .1 mL. Record all measured values in the data chart for Part C in the observations section of your lab report. 4. Return the solid object to the area designated by your instructor.

The data chart for Part C should contain the following information: (* refers to calculated or theoretical values) A. Mass of the solid object E. *Density of solid (experimental) B. Original volume of water F. *Specific gravity of solid (experimental) C. Volume of water and solid G. *Specific gravity of solid (theoretical) D. *Volume of solid H. *Percent error for specific gravity Part D. Calibration

1. Use a dropper pipette to determine the number of drops in 5.0 mL of water. Hold the dropper...