Investigating Chemistry

Lesson 1 - Properties of Matter

OBJECTIVE

Students will explore the properties of the three common states of matter, learn about the size of atoms, and observe chemical reactions.

AAAS BENCHMARKS COVERED*

Heating and cooling cause changes in the properties of materials. Many kinds of changes occur faster under hotter conditions. Materials may be composed of parts that are too small to be seen without magnification. When a new material is made by combining two or more materials, it has properties that are different from the original materials. For that reason, a lot of different materials can be made from a small number of basic kinds of materials. Scientific investigations may take many different forms, including observing what things are like or what is happening somewhere, collecting specimens for analysis, and doing experiments. Investigations can focus on physical, biological, and social questions.

​COMMON CORE ELA STANDARDS COVERED:

Article : “AN ATOM APART” -Common Core ELA RI.4.1 Key Ideas and details : Refer to details and examples in a text when explaining what the text says explicitly and when drawing inferences from the text .RI.4.10; RI.5.10: Range of reading and level of text Complexity: by the end of the year , read and comprehend informational texts, including history, social studies ,science and technical texts at the high end of the grades 4-5 text complexity band independently and proficiently.L.4.4; L. 5.4: Vocabulary Acquisition and Use: Determine or clarify the meaning of unknown and multiple meaning words and phrases based on grade 5 reading and content choosing flexibly from a range of strategies.

NGSS STANDARDS COVERED: 5-PS1-1

Lesson Outline

Introduce the new unit.Observe the solid (baking soda). Record observations on the "Observations" worksheet in the Student Booklet. Encourage students to use all their senses except taste.

Distinguish between observations and inferences.

Observe the liquid (vinegar). Record observations in Student Booklet.

Mix baking soda and vinegar in the jar. Contrast the gas in the empty jar with the gas in the baking soda/ vinegar jar.

Record observations in Student Booklet.

Help students turn their observations into interpretations.

Assign "Observations and Interpretations" worksheet in Student Booklet.If doing the lesson in two parts, stop here.Review Student Booklet.

Have students cut strips of paper in half over and over again.Use the "How Big is an Atom?" poster to connect the cut paper strips with the size of an atom. Stress that atoms and molecules are incredibly small.

Go over the experiment "Changes" in Student Booklet. Students will use the lids in Lesson 2 after the liquid evaporates.

Allow time for students to complete the experiment.

Lesson 2 - Matter Can Change

OBJECTIVE

Students observe the difference between a physical and chemical change, measure a sign of a chemical change, and explore a substance with properties of both a liquid and solid.

AAAS BENCHMARKS COVERED*

When a new material is made by combining two or more materials, it has properties that are different from the original materials. For that reason, a lot of different materials can be made from a small number of basic kinds of materials. Results of similar scientific investigations seldom turn out exactly the same. Sometimes this is because of unexpected differences in the things being investigated, sometimes because of unrealized differences in the methods used or in the circumstances in which the investigation is carried out, and sometimes just because of uncertainties in observations. It is not always easy to tell which.Some features of things may stay the same even when other features change. Some patterns look the same when they are shifted over, or turned, or reflected, or seen from different directions.Things change in steady, repetitive, or irregular ways-or sometimes in more than one way at the same time. Often the best way to tell which kinds of change are happening is to make a table or graph of measurements.

​COMMON CORE ELA STANDARDS COVERED:

NGSS STANDARDS COVERED: 5-PS1-2

Lesson Outline

Complete the top half of the worksheet in the Student Booklet entitled "Matter Can Change-Changes". Students will test the dried substances from Lesson 1B with vinegar. The vinegar lid will not react while the water lid will react.

Explain that the mixing baking soda and vinegar was a chemical reaction and mixing the baking soda and water was a physical reaction. The baking soda that had been mixed with water was still baking soda, the change was just physical. The molecules of the baking soda that had been mixed with vinegar had been broken down and combined with molecules from the vinegar to make new molecules of a completely different substance.

Discuss the differences between chemical and physical reactions.Assign the "Matter Can Change-Physical/Chemical" worksheet in Student Booklet.

Complete the next experiment in Student Booklet and create a graph to measure temperature change (if any) of your chemical reaction. Allow students to make as many decisions about how they will do the experiment as they can.If you are doing the lesson in two parts, break after students have planned their experiment and have them complete the experiment during the second part.

Mix cornstarch and water to make a non-Newtonian fluid that has characteristics of both a solid and a liquid. About 1 1/2 cups water and 1 pound cornstarch makes enough for about 10 students.

Lesson 3 - But Mass Doesn’t

OBJECTIVE

Students will build a balance scale and use it to find that volume can change but mass doesn’t.

AAAS BENCHMARKS COVERED*

No matter how parts of an object are assembled, the weight of the whole object made is always the same as the sum of the parts; and when a thing is broken into parts, the parts have the same total weight as the original thing. Throughout all of history, people everywhere have invented and used tools. Most tools of today are different from those of the past but many are modifications of very ancient tools. Measuring instruments can be used to gather accurate information for making scientific comparisons of objects and events and for designing and constructing things that will work properly.

COMMON CORE ELA STANDARDS COVERED:

NGSS STANDARDS COVERED: 5-PS1-3

COMMON CORE MATH STANDARDS COVERED:

​Students build a balance scale and use it to find that volume can change but mass doesn’t. This lesson provides a perfect opportunity to go over some of the terms they will be using for measurement. We’ve included terms and definitions here and in the student workbook .

Lesson Outline

Review worksheet "Matter Can Change-Changes Physical/Chemical in Student Booklet.

Show students the reaction of litmus paper to acids and bases. Litmus paper is specially treated with a powder derived from lichens that change to red with increased acidity. Lichens are fungus that grow with algae resulting in a composite organism the forms a crust like growth on rocks and trees.

Hand out pieces of Galaxy Gold paper, soap pieces, and cups with water to students. Since soaps are bases, students can use dampened soap to write on their paper.

Contrast mass and weight. Mass is not dependent on gravity, weight is.

Make balance scales.

If you are doing this lesson in two parts, break here.

Do the activity worksheet in Student Booklet "But Mass Doesn't-Using a Balance Scale 1".

The mass of 10 ml of water and 10 ml of salt is found. When they are mixed, the volume is only about 15 ml but the total mass is the sum of the original masses.

Do the activity worksheet in Student Booklet "But Mass Doesn't-Using a Balance Scale 2". The mass of 1/4 tsp sodium polyacrylate is found. When combined with 10 ml water, the volume increases dramatically but the mass remains the sum of the original masses.

Lesson 4 - Density Matters

OBJECTIVE

Students learn why some things float and some things sink.

AAAS BENCHMARKS COVERED*

Tables and graphs can show how values of one quantity are related to values of another.

Lesson Outline

Give each student a piece of aluminum foil and six washers.

Give each group a container of water.

Challenge students to build two boats, one that sinks with three washers and one that floats. Students should record their observations in Student Booklet lesson 4 "Density Matters-Floating and Sinking 1".

Discuss the differences between the boats. Demonstrate the difference in amount of water displaced by a sinking boat and a floating boat. Help students understand that a floating boat displaces more water than a sinking boat.

Have each group prepare cups. One will be filled to the top with water. The best way is to put the lid on the bottom of the container of water. Fill a cup with water, and push it down onto the lid. There should be no air in the cup.

Prepare cups with washers. One will have one washer, one with two washers, one with three washers, all the way up to 7 washers. Put lids on till cups.Have students follow directions in Student Booklet lesson 4"Density Matters-Floating and Sinking 2.

Students will find the mass of each cup, check to see if each cup floats or sinks, and then compare the masses of each cup to the mass of the cup of water. Students should discover that those cups that weigh more than the cup of water sink and those that weigh less float.

Discuss why things float and sink — things that float weigh less than an equal volume of water (or whatever they're floating in). If an object weighs more than an equal volume of water, the object will sink.If possible, demonstrate that diet sodas float while sugared sodas sink. Discuss what that tells them about the cans of soda (because they have an equal volume, the sugared soda must weigh more than the diet soda).

Also try fruits and vegetables. Be sure to try an unpeeled orange!

Lesson 5 - Polymer Lab

OBJECTIVE

Students will identify properties of three different recipes of polymers and create a new recipe that has specific properties.

AAAS BENCHMARKS COVERED* When a new material is made by combining two or more materials, it has properties that are different from the original materials. For that reason, a lot of different materials can be made from a small number of basic kinds of materials.Measure and mix dry and liquid materials (in the kitchen, garage, or laboratory) in prescribed amounts,exercising reasonable safety.Keep a notebook that describes observations made, carefully distinguishes actual observations from ideas and speculations about what was observed, and is understandable weeks or months later.

COMMON CORE MATH STANDARDS COVERED:​

NGSS STANDARDS COVERED: 5-PS1-4

*AAAS (American Association for the Advancement of Science) Project 2061 established benchmarks and standards that informed many of the science standards developed by individual states as well as the standards proposed in the Next Generation Science Standards currently being considered for adoption in states and school districts. The Center for Hands on Learning has created Teacher’s Editions for specific states where applicable. If you’re a teacher in New Mexico your Teacher’s Edition will feature NM Science Standards. Understanding that adoption of Next Generation Science Standards are being considered in New Mexico we have established the commonality of New Mexico Science Standards with those recommended by Next Generation. Our “Journey into Science” series covers those standards recommended by Next Generation grades kindergarten through fifth grade although there may be differences regarding the grade level at which subjects are initially introduced. Your Teacher’s Addendum will note the commonality that currently exists between New Mexico Science Standards and those standards recommended by Next Generation. Investigating Chemistry for example is aligned with NM State Science Standards for Physical Science for 4thgrade. Next Generation introduces these Physical Science Standards in 5th grade.We have included Common Core ELA and Math worksheets and have noted the standards in both 4th and 5th grade that are met by doing the exercises in these worksheets.

Lesson Outline

Explain the task - follow the directions in Student Booklet lesson 5 "Polymer Lab" to make polymers and gather data on the properties of each one. Record observations on worksheet in Student Booklet. Then use that information to make a polymer that is bouncier or stretchier. Record recipe and observations in Student Booklet lesson 5 "Polymer Lab-Polymer Challenge".

After students have made polymers, explain why polymers form.