Chemistry project

Project 1

Evaluation 31

Chemistry 1 (SCIH 031 062)

Be sure to include ALL pages of this project (including the directions and the assignment) when you send the project to your teacher for grading. Don’t forget to put your name and I.D. number at the top of this page!

This project will count for 6% of your overall grade for this course. Be sure to read all the instructions and assemble all the necessary materials before you begin. You will need to print this document and complete it on paper. Feel free to attach extra pages if you need them.

When you have completed this project you may submit it electronically through the online course management system by scanning the pages into either .pdf (Portable Document Format), or .doc (Microsoft Word document) format. If you scan your project as images, embed them in a Word document in .gif image format. Using .gif images that are smaller than 8 x 10 inches, or 600 x 800 pixels, will help ensure that the project is small enough to upload. Remember that a file that is larger than 5,000 K will NOT go through the online system. Make sure your pages are legible before you upload them.** Check the instructions in the online course for more information.

Project 1- Candy Bar Density Lab

Purpose: This lab is intended for students to investigate the principles of mass, volume, and density and to relate the principle of buoyancy in comparison to candy bar density and to understand the importance of accuracy in measurements and applying mathematical principles to scientific procedures.

Laboratory Materials List

The Projects in this course require special materials. Some of these materials are found in the Chemistry 1 Lab Kit and some will need to be provided by you, the student. Before doing a project, gather all the items you will need for that specific project and out them on a clear work space.

Student Will Supply Materials in Kit

pencil balance (for measuring mass)

paper

calculator

soft tissue or paper towel

ruler (for measuring volume)

2 different kind of candy bars (any kind that can be split in half)

Part A – Procedure (possible 10 points-charts must be filled out correctly)

	Mass	Volume	Density
Definition
How to find		Formula for Regular Shaped Objects:	Formula:
Units

Part B – Analyze (possible 20 points)

Directions:

· Use the balance to record an accurate mass for each candy bar. Make sure to zero out the balance before each measurement is taken.

· Use the ruler and calculator to find the volume of each candy bar.

· Calculate density after you have found mass and volume

Steps to take for mass:

1. Place half of a soft tissue (or paper towel) on the pan of the balance.

2. Zero out balance with soft tissue (or paper towel) on pan and place unwrapped candy bar on it.

3. Find the candy bar’s mass to the nearest tenth (0.1) g if possible. If not, to the nearest gram and record below. Note: if you have the balance that comes with your kit, your measurement will be to the nearest gram.

Steps to find volume:

1. Measure using the formula you identified above in part A

2. Calculate to the nearest tenth (0.1) cm3 and record below

Density of Whole candy bar #1: Include proper units with each measurement.

Mass	Volume	Density
Round to nearest 0.1	Round to nearest 0.1	Round to nearest 0.1

Density of Whole candy bar #2: Include proper units with each measurement.

Mass	Volume	Density
Round to nearest 0.1	Round to nearest 0.1	Round to nearest 0.1

Density of half candy bar #1: Include proper units with each measurement.

Mass	Volume	Density
Round to nearest 0.1	Round to nearest 0.1	Round to nearest 0.1

Density of half candy bar #2: Include proper units with each measurement.

Mass	Volume	Density
Round to nearest 0.1	Round to nearest 0.1	Round to nearest 0.1

Part C – Conclusion (possible 20 points)

1. When finding the volume for half the candy bar which variables did not change and why?

2. What did you record about the densities of each candy bar? Write complete sentences explaining any similarities or differences that were noted.

3. Explain how buoyancy and density are related in why some things float and others sink. To answer this question completely, use additional resources such as the internet or library. MUST cite your source(s).

4. Water’s density is 1.0 g/cm3. Knowing this information, would either of your candy bars sink or float if placed in water? Explain using complete sentences.

5. If measured accurately, your densities should be very close to each other when comparing the whole candy bar to the same half candy bar. What factors would influence your calculations between the densities to be completely different (assuming your measurements weren’t close)? Make a list.

This project can be submitted electronically. Check the Project page under “My Work” in the UNHS online course management system or your enrollment information with your print materials for more detailed instructions.