MC	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

Baking soda and vinegar are mixed in a bottle. A balloon placed over the top fills and expands the gas. How do you know a chemical reaction has taken place?

a. A solid and a liquid have been mixed together.

b. A new substance has formed.

c. The balloon has stretched and changed shape.

d. The bottle had not been changed.

Correct Answer: b

MC	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

Bread placed in a toaster turns brown then black if left too long. What is needed for this chemical change to take place?

a. heat energy had to be added

b. heat energy had to be taken away

c. a certain amount of time had to pass

d. the bread had to be taken out of the wrapper

Correct Answer: a

MC	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

A pair of scissors left outdoors has rusted. What evidence shows that a chemical reaction has taken place?

a. They are hard to use.

b. The sun has warmed them.

c. They are dirty.

d. They have turned orange.

Correct Answer: d

MC	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

How are fireworks examples of chemical reactions?

a. They are made of chemicals?

b. They change color and require energy.

c. It is easy to reverse the explosion.

d. They are only used for special occasions.

Correct Answer: b

I	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

Teacher demonstration: Combine 1 tsp. baking soda and 1 T. vinegar in a glass bottle. Quickly place a balloon over the opening of the bottle. Students should observe that the balloon will expand.

After observing the demonstration, students should respond to the following question:

Based on this demonstration, did a physical or chemical change occur? What evidence did you observe to support your answer?

Scoring Guide:

3 points Chemical change occurred. Balloon expanding indicated that baking soda and

vinegar combined in a chemical reaction to form a gas.

2 points Chemical change occurred. Incomplete explanation.

1 point Chemical change occurred. No explanation.

I	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

Mark made observations as he watched a white candle burn.  Use his data to answer the next two questions.

Time	Observations
0 minutes	Candle is lit, black smoke rises
1 minute	Flame glows red and orange
2 minutes	Wax starts to melt and run down candle
3 minutes	Candle is shorter than when it started
4 minutes	Hot gases are rising above the candle

1.  Which of MarksÕ observations would show that a burning candle is a chemical reaction?

a.  black smoke is given off, hot gases are rising

b.  the wax starts to melt

c.  the candle is white and made of wax and a wick

d.  time passes one minute at a time

2.  Which of MarksÕ observations would show that a burning candle has physical changes?

a.  black smoke is given off, hot gases are rising

b.  the wax starts to melt

c.  the flame glows red and orange

d.  time passes one minute at a time

Correct Answers:

1. a

2. b

E	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

What is a chemical reaction? What is one way you know it has occurred?

Correct Answer:

When two or more substances come together to form something new. It cannot be reversed or undone easily or energy is required or released.

E	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

Explain why burning a piece of wood is a chemical reaction.

Correct Answer:

The wood combines with air (oxygen in air) to form new substances such as ash and smoke. Energy is given off. The new substances cannot be put back together to form wood.

P	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

Activity Description:

Students will watch a series of demonstrations and determine whether a chemical change has occurred. They will explain their reasoning.

Materials Needed:

Baking soda and vinegar, bromothymol blue or other acid/base indicator, acidic and basic solutions (acidic=vinegar, soda pop, lemon juice, basic=soaps, window cleaner), clear glass containers, flour, sand, match, paper, wax, heat source.

Prior to Assessment:

Students should have had hands-on experience with physical and chemical reactions. They should have a good understanding of the difference between physical changes and chemical reactions.

Time Needed:45 minutes

Procedure:

1. Students need a paper folded in half the long way. The two resulting columns should be labeled: ÒPhysical change/Chemical reactionÓ and ÒWhyÓ.

2. As the teacher demonstrates the following changes, the students should record whether they think a physical change or a chemical reaction has occurred and why they think so. The reactions listed are examples, others may be used if materials are more accessible.

a. Mix 2 tsp baking soda with 50 ml of vinegar.

b. Mix equal amounts of flour and sand in a clear glass container.

c. Add an acid or base to bromothymol blue. (water that red cabbage has been boiled in also makes an excellent acid or base indicator)

d. Burn a piece of paper (have a dish with water ready to catch the remains!)

e. Melt some wax in a clear glass container.

Scoring Guide:

Student receives 2 points for each correct answer and one correct reason given.

a. Chemical reaction ∆ a new substance, the gas, is formed. Energy is given off, not easily reversible

b. Physical change ∆ no new substance is formed, easily reversible, no energy exchange

c. Chemical reaction ∆ a new substance (the colored material) is formed.

d. Chemical reaction ∆ two new substances, the gas and the black paper remains are formed. Energy is given off, not easily reversible.

e. Physical change ∆ no new substance is formed, easily reversible.

MC	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

5 grams of baking soda and 20 grams of vinegar are added together. A bubbling reaction starts. When it is over, the solution weighs 24 grams. Why has the weight changed?

a. a gas has formed and left the mixture.

b. The vinegar has evaporated.

c. The new solution is lighter.

d. Baking soda is lighter when dissolved in vinegar.

Correct Answer: a

E	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

50 grams of vinegar and 2 grams of baking soda are mixed together. A bubbling reaction takes place. The mixture is weighed again and now weighs 49 grams. Where did the missing weight go?

Correct Answer:

The gas that escaped from the mixture contained the missing weight.

E	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

Susan adds 50 grams of one substance to 50 grams of another substance. A color change occurs and the new weight is 95 grams. Susan thinks a gas may have formed and left the mixture. Is she right? Why?

Correct Answer:

Yes, she is right. Substances do not lose weight during chemical reactions but they can forma gas. Gases are usually invisible, and they do have weight.

MC	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

How might reactions with burning be important in your daily life?

a. Burning creates food for people.

b. Modern medicines depend on burning.

c. Most clean water is created by burning.

d. Burning fuels supplies heat and light.

Correct Answer: d

MC	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

The food we eat is nearly always cooked before eating. Why?

a. It has to be cooked for us to chew it.

b. Food cannot be digested if eaten raw.

c. Cooking makes chemical and physical changes in food.

d. Food changes color when it is cooked and looks more appealing.

Correct Answer: c

MC	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

Which of these foods have been through a chemical change?

a. carrots cut up in a salad

b. vinegar and oil mixed together

c. juice and water stirred together

d. sugar and cream boiled to make a sauce.

Correct Answer: d

E	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

You are cooking in your kitchen and think you have made a chemical reaction by adding two substances together. How will you know when a chemical reaction occurs?

Correct Answer:

When a color change occurs, a gas is given off or energy is given off or absorbed.

MC	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

A student watches an ice cube melt into a puddle of water. Has a chemical reaction taken place?

a. Yes, a gas has been given off.

b. Yes, the color has changed.

c. No, water does not react chemically.

d. No, no new substances have formed.

Correct Answer: d

I	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

Substance	Physical Change	Chemical Change
Sugar	Poured into cup	Cooked into candy
Nail	Hammered into wood	Rusted from rain
Baking soda	Measured by a spoon	??

Which of these will correctly complete the chart showing a chemical change with baking soda?

a. poured through a funnel

b. mixed with vinegar

c. stirred in the can

d. placed in a balloon

Correct Answer: b

I	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

The following students were interested in the differences between chemical and physical changes.

Jamie read about physical and chemical changes in a science book and then tried an experiment in which she placed bread in the toaster for a long time to see if she could create a chemical reaction. It worked! Burning the toast caused a new substance to form on the outside of the toast. She explained what she discovered to her teacher the next day.

Mike was interested in what types of materials he could use to create physical and chemical changes. He experimented with various substances to see if he could produce a chemical reaction. He found that if he mixed baking soda and vinegar a gas was produced. A chemical change had occurred.

When Ryan was visiting his dad in Florida, he noticed that his dadÕs car was rusting. He spent hours in the garage with his dad sanding off the rust and repainting the car. When his teacher showed a video on physical and chemical changes, Ryan realized that the rust was a result of a chemical change. He experimented with metal and water to try to find a way to keep his dadÕs car rust free.

1. Which of these students used an appropriate scientific investigation to learn about physical and chemical reactions?

a. Jamie and Mike

b. Mike only

c. Jamie, Ryan, and Mike

d. Ryan and Jamie

2. Explain how you made your decision.

Correct Answers:

1. c

2. Students should understand that all three students used an appropriate method for investigation. They do not have to use the Òscientific method.Ó The students used a variety of methods for investigating. There is not just one scientific method.

I	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

Listed below are examples of physical and chemical changes. Identify and sort each change into the appropriate column.

1. Cutting a piece of paper

2. Mixing water and cocoa

3. Rust forming on a ship

4. Boiling water

5. Fireworks exploding

6. Melting ice cream

7. Making toast

8. Water freezing

9. Crushing a can

10. Melting sugar to make caramel

11. Burning wood

Physical Changes

Chemical Changes

Correct Answers:

Physical Changes: 1, 2, 4, 6, 8, 9

Chemical Changes: 3, 5, 7, 10, 11

MC	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

While cooking, Amber combined vinegar and milk, which slightly thickened. If she used baking soda instead of milk, which of the following would happen between baking soda and vinegar?

a. It would also become slightly thickened.

b. It would not mix well together.

c. It would bubble and form a gas.

d. It would harden to become a solid.

Correct Answer: c

MC	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

Which of the following is true about chemical reactions?

a. Chemical reactions between two substances are easily reversible.

b. Anytime a solid and liquid are combined, they always form a solid.

c. Changing one of the materials in a chemical reaction will usually change the results.

d. Anytime vinegar is used in chemistry, a gas is always released.

Correct Answer: c

P	5^th Grade	Standard: 01
Objective: 03. Investigate evidence for changes in matter that occur during a chemical reaction.
ILO:

Red Cabbage Indicator

Activity Description:

Students will investigate how common household products can change the color of a neutral cabbage base indicator. As they change the different materials to be used, they will hypothesize and predict the color change. Remind students that an acid will turn PINK and a base will turn GREEN.

Materials:

Red cabbage indicator (made by mixing shredded red cabbage with water and boiling for a few minutes. Strain the juice and store in refrigerator until ready to use.), 5 test tubes and rack per group, small amounts of the following materials to try: milk, lemon juice, baking powder, laundry soap, vinegar.

Time Needed:

50 minutes

Procedure:

1. Students will set out materials to test as acids and bases.

2. They will make a chart to write their hypothesis of what they think will happen, then record the results.

3. Students will combine the different materials with red cabbage juice and write down their results.

4. If desired, students may order the test tubes from strongest acid to strongest base.

Scoring Guide:

0 No attempt made, worksheet not filled out

1 Student chart partially filled out, no predictions

2 Student chart partially filled out with predictions

3 Student chart mostly complete

4 Student chart complete with results recorded accurately