Chemistry Assignments

Assignment: Properties

i will send  the images separately 

• For each of the objects list six physical properties of the object.
• Identify each property as extensive (E) or intensive (I) and describe how you know it is an intensive or extensive physical property.
• Then, select one property you identified for each object and describe, in detail, how you would test that property.
• For example, if you determined that a metal rod is very dense, how would you measure its density?

Record your answers in the template provided and submit them to the Assignment: Properties link for grading. For more information on how this will be graded, please view the grading rubric.

Section Warm-Up

Journal: Seltzer in Water

[img alt="A seltzer tablet in water." src="http://static.k12.com/eli/bb/334/2_23579/1_124930_4_23583/634a35ff424938d285f15dd8d832abf31af3e831/media/33db7dd8daaa6dc72d1d5e4ca5bce6198a5e020e/mediaasset_630661_1.jpg" title="A seltzer tablet in water.">

In your house, grab a small cup of water, some seltzer tablets, and a thermometer. Over-the-counter heartburn or cold remedies will work for the seltzer tablets—just look for the ingredients, sodium bicarbonate and citric acid.

• Before doing anything, write down some physical characteristics of each substance (the water and the tablet).
• Then, take the temperature of the water.
• Now, add the seltzer tablets to the water, leaving the thermometer in the water.
• Answer the following questions in your journal:
  • What happens?
  • What does the final product look like?
  • Is it still water? How do you know?
  • Did a physical change take place? How do you know?
  •  Was there a temperature change during the event?

Write down your observations and answers to these questions in your journal and submit to the Journal: Seltzer in Water assignment link for grading. For more information on how this assignment will be graded, please view thejournal rubric.

Lab Introduction

Paper is an amazing material. Most paper is made from the cellulose fiber obtained from trees or other woody plants. Unlike wood, you can fold paper, tear it, or dissolve it in water. Each of these changes made to the paper is classified as a physical change.Paper, like the wood it is made from, can also burn in the presence of oxygen and enough heat– this is considered a chemical change. In this laboratory experiment, you will observe the physical and chemical changes that a substance can undergo

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Lab Instructions

Time Requirements: approximately one hour

Procedures:

Follow the lab instructions to perform the laboratory investigations. As you perform your experiment, record everything in this lab instruction sheet.

Use the checklist to make sure all parts of the lab are complete.

1. Read through the lab introduction.
2. Complete the pre-lab questions.
3. Read through the lab instructions completely before setting up the materials for your experiment.
4. Conduct the experiment.
5. Complete the calculations (if any) and answer the post-lab questions

Lab Objectives

After you have completed this laboratory, you will be able to:

1. Recognize the differences between chemical and physical changes.
2. Determine if a change is physical or chemical.

   Lab: Chemical and Physical Changes

   Congratulations on completing this lab! In this lab, you learned about:

   1. Laboratory procedures to separate and combine chemicals
   2. The physical and chemical properties of a substance

   Now it is time to turn in your lab instruction sheet. Make sure you have filled in all the relevant information and answered all the post-lab questions. Submit your lab report to the Lab: Chemical and Physical Changes assignment link for grading. For more information on how this assignment will be graded, view the Lab Rubric.

Exploratory Activity: Chromatography

Materials:Forensic scientists use chromatography on ink pens to tell if a document was written with a specific pen. This can provide direct evidence in many types of cases. For example, if a ransom note was found, forensic scientists would analyze the ink using chromatography.If a suspect was found with a pen that showed the same chromatography pattern, the forensic scientists would have strong evidence to suggest that suspect wrote the ransom note. Let’s see how forensic scientists would test a pen. You will need only a few simple household materials.

• Two coffee filters
• Two different black markers (NOT permanent markers)
• Saucer
• Water
• Activity Worksheet

Procedure:

• Using one of the black markers, place a dot in the center of the filter paper.
• Place the filter paper on the saucer.
• Put a few small drops of water on the spot.
• Wait a few minutes…what did you see?
• Now, using the other black marker and the other coffee filter, repeat the procedure. What did you see this time?
• Many black inks are made up of several dyes. Explain any differences you saw between the two markers.
• Did the components of the inks separate differently?
• Are any of the component colors the same in both of your markers?

Answer these questions in the exploratory activity worksheet and submit your worksheet to the Exploratory Activity:Chromatography assignment link for grading. For more information on how this assignment will be graded, please view the rubric.

Lab Introduction

You’ve just poured yourself the last bowlful of your favorite breakfast cereal – Up & Atom. While working your way through the first few spoonfuls, you discover, from the information on the box, that each bowl contains your complete daily allowance of iron. Is there some way you can prove the cereal manufacturers statement? You’ve already added milk to the cereal. How would you separate out this mixture to measure the iron content? This lab will walk you through some of the processes for separating mixtures.

Lab Objectives

After you have completed this laboratory, you will be able to:

1. Use physical properties to separate the components of a mixture.
2. Use laboratory techniques to separate the components of a mixture.

Lab Instructions

Time Requirements: approximately 1.5 hour

Procedures:

Follow the lab instructions to perform the laboratory investigations. As you perform your experiment, record everything in this lab instruction sheet.

Use the checklist to make sure all parts of the lab are complete.

1. Read through the lab introduction.
2. Complete the pre-lab questions.
3. Read through the lab instructions completely before setting up the materials for your experiment.
4. Conduct the experiment.
5. Complete the calculations (if any) and answer the post-lab questions