Lab #2

Name Date

Period Due Date:_____

Mrs. Luna Lab Min:______

Density of Solids and Liquids

Lab # __ ______

Introduction: Density is the term used to describe the relationship between the mass of an object and its volume. Under given conditions of temperature and pressure, the density of a material is constant. The density of any earth material can be determined by measuring its mass and volume and using the equation:

Density = Mass

Volume

Objective: You will be able to calculate the densities of different materials and recognize that density is one if the most important properties of matter. The masses of each object will be determined by using a triple beam balance.

The volumes of the solids will be calculated either by linear measures (L x W x H = V³) or by determining the amount of water displacement by submerging the object in water. Gold has a density of 19.0g/mL, the average rock had a density of 3.9g/mL and water has a density of 1.0 g/mL. 1g/ml means that 1 mL(or cm³) of water has a mass of 1 gram or 1 liter of water has a mass of 1 kg.

Don’t forget when reading the graduated cylinder to read the bottom of the meniscus as shown below.

Figure 1: Graduated Cylinder

Materials: Pencil

Paper

ESRT

Ruler

Triple Beam Balance

Calculator

Unknown Objects

Your Notes

Vocabulary:

Mass:________________________________________________

Weight:______________________________________________

Volume:______________________________________________

Pre-Lab Questions:

Which is more dense, solids or liquids?_______________________

Which is more dense Ice or Water? _________________________

Which formula do you use to find the Volume of a solid? ______

What is the formula to find the mass of an object? ________

What is the formula to find the volume of an object? _________

What is the formula to find Percent Error of Deviation?

________________________________________________

Procedure:

1. Measure the mass of each object using a scale.

Your answer will be in will be in grams(g)

2. Find the volume of each object using the metric ruler and the formula: length x width x height (v = l x w x h ). Your answer will be in cm³

3. Calculate the density of each object by dividing the mass by the volume.

Mass/Volume = Density

4. Record these data on Report Sheet 1.

5. After completing Report Sheet 1 obtain the accepted densities for each item from your teacher.

6. Using the density values and the accepted values calculate the percent deviation from accepted values for each item.

7. Record your calculations and answers on Report Sheet 2.

Report Sheet #1

1. Aluminum Bar Mass = _____________ g L = _______ cm W = _______cm H= _______cm Volume = ________cm³ Density = ________g/cm³	2. Aluminum Cube Mass = ________________ L = ________ W = _______ H = _______ Volume = ___________ Density = _________
3. Wood Bock Mass = _____________ L = ______ W = ______ H= _______ Volume = _____________ Density = _____________	4. Alumium Sphere Mass = ___________ L= ________ W=________ H=________ Volume = _______ Density = _______
5. Halite Mass = _________ L = _______ W=_______ H=_______ Volume = ____________ Density = ____________	Galena Mass = __________ L = _______ W= _______ H=________ Volume = ________ Density =_________

Area for Mathematical Computation

Part 2

Density of a Solid and a Liquid

Report Sheet 2

Directions: Determine the % Error for Each Object Density.

Show all work

Label with the correct units.

Aluminum Bar: Your Value__________ Accepted Value__________ % Deviation_____________	Aluminum Cube: Your Value__________ Accepted Value__________ % Deviation_____________
Aluminum Sphere: Your Value__________ Accepted Value__________ % Deviation_____________	Wooden Block Your Value__________ Accepted Value__________ % Deviation_____________
Halite: Your Value__________ Accepted Value__________ % Deviation_____________	Galena: Your Value__________ Accepted Value__________ % Deviation_____________

Discussion Questions: (Answer in Complete Sentence)

1. What is the effect of shape on the density of samples of the same materials?

2. The aluminum bar is cut in half. What is the density of each half compared to the original density of the bar?

3. Of the three phases of matter, which phase has the greatest density for most substances.

4. Water is an unusual earth material because it us the densest at which phase and at which temperature.

5. There is water on the pan of the scale as you measure the mass of a mineral. If you were to ignore the water, what would be the effect on your density calculations?

6. Why is water in its solid phase so unusual when its compared to other solids?

List some of the characteristics of water in the solid phase.

Conclusion Question: Answer in complete sentences

Describe the procedure for determining the density of Solids and Liquids

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