Name. Pre-Test. Directions: Circle the T if a statement is true or F if it is false (F). 1. Matter always stays the same.

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1 1 Pre-est Directions: Circle the if a statement is true or if it is false (). 1. Matter always stays the same. 2. A physical change is a change in size, shape or phase of matter, without the matter changing chemically.. 3. emperature can play a big role in physical changes. 4. In a physical change, matter cannot change its shape. 5. he ability to burn is a chemical property called flammability. 6. A chemical change is a process by which a certain substance becomes a different substance. 7. In a chemical change, the same substance is formed. 8. Chemical changes occur at the same speeds. 9. Chemical reactions occur when two or more substances combine to form a new substance. 10. Photosynthesis is an important chemical reaction on earth.

2 2 Video Quiz Directions: ill in the blank with the correct word from the list at the bottom of the page. Not all words from the list will be used. 1. Ice being broken into small bits is an example of a change. 2. In a physical change the matter does not change. 3. In a chemical change a substance is formed. 4. A chemical is a way to describe how matter reacts with other matter. 5. lammability is the chemical property describing how a substance. 6. A clue that a chemical change is occurring in a burning flame is that is given off. 7. Chemical changes occur at speeds. 8. is the substance produced by iron reacting with oxygen in the air. 9. A chemical is the chemical change in which one or more substances change. 10. is a chemical reaction in green plants that produces energy and oxygen. acetic acid burns chemically decomposition different energy flammability freezes heat new old photosynthesis physical property reaction rust sodium bicarbonate solid

3 3 Discussion Questions Directions: Answer the following questions in the space provided or out loud. 1. What is a physical change? 2. What are some examples of physical changes in matter? 3. What is a chemical change? 4. What are some examples of chemical changes in matter? 5. What is a chemical reaction? 6. Write out an example of a chemical reaction. 7. What are some physical changes that occur at school? At home? In nature? 8. What are some chemical changes that occur at school? At home? In nature?

4 4 Vocabulary Exercise Direction: Match the vocabulary word with its correct definition by drawing a line from the word to the definition. physical change A. A chemical property describing how a substance burns. chemical property B. A change in the size, shape, or phase of matter, without the matter changing chemically. chemical change C. Process of plants producing energy, oxygen, and water by taking in carbon dioxide, water, and the sun s energy. rusting D. A way to describe how matter reacts with other matter. chemical reactions E. A chemical change in which one or more substances is changed. flammability. When iron reacts with oxygen, it corrodes to form a new substance, and is an example of a slow chemical change. photosynthesis G. he process by which a certain substance becomes a different substance.

5 5a Observing Changes in Matter Objective In this activity, you will create different changes, and identify them as physical or chemical. Materials Data able safety glasses paper baking soda vinegar dropper limestone salt container of water pencil pencil sharpener ph paper rusty piece of iron non-rusty piece of iron clay ice cube ant-acid tablets Procedure 1. In this activity, you will create both physical and chemical changes. Before you begin the activity, put on the safety glasses provided by your teacher, and wear them during the entire activity. 2. Your teacher has set up several stations throughout the classroom. At each station, you will observe or create a change. Perform the task, and decide if the change is a physical change or a chemical change, then fill in your answer in the data table. Station 1 - A piece of paper is provided in this station. ear the paper into many smaller pieces. Is this a physical or chemical change? Station 2 - A small amount of baking soda and a dropper with vinegar is at this station. Place small drops of vinegar onto the baking soda. Record your observations. Is this a physical or chemical change? Station 3 - At this station, a small white rock, called limestone, is provided, as well as a dropper and vinegar. Place a drop of vinegar on the limestone and record your observation. Is this a physical or chemical change? Station 4 - A teaspoon of salt, a glass of water, and a spoon are provided. Stir the salt into the water. Is this a physical or chemical change?

6 5b Observing Changes in Matter Station 5 - ake the pencil provided and sharpen it at the pencil sharpener. Is this a physical or chemical change? Station 6 - A small piece of ph paper is provided. his is special paper used to determine acidic or basic a substance is. Place the tip of the paper in the vinegar solution. Observe any color change on the paper. Is this a physical or chemical change? Station 7 - wo pieces of iron are at this station. One is a silvery color; the other piece of iron has been left in the air for a long period of time, and is an orange color. Has this piece of iron undergone a physical or chemical reaction? Station 8 - Mold the piece into the shape of a snake. Is this a physical or chemical change? Station 9 - Sitting in a cup are several ice cubes. As these ice cubes are exposed to the air in your classroom, are they undergoing a physical or chemical change? Station 10 - A white ant-acid tablet is provided, along with a cup of water. Place the table in the water, and observe the reaction. Is this a physical or chemical change? Data able (next page) Conclusion As a class, discuss any problems you had identifying the different types of changes. Discuss any other common changes that take place in the classroom on a daily basis. Discuss the clues you used to decide whether the change was a physical change or a chemical change.

7 5c Observing Changes in Matter Data able Station Number Observation Physical or Chemical Change? 1 - Paper 2 - Baking soda and vinegar 3 - Limestone and vinegar 4 - Salt and water 5 - Pencil and sharpener 6 - ph paper and vinegar 7 - two pieces of iron 8 - clay 9 - ice cubes 10 - Ant-acid tablet and water

8 6a Observing Changes in Your Environment Objective In this activity, you will identify the many different physical and chemical changes that occur in your home, school, and neighborhood. Materials Data able pencil Procedure 1. Believe it or not, there are dozens, if not hundreds, of physical and chemical changes that occur around you everyday. or example, on your way to school you may have traveled on a bus or in a car. he engines in these vehicles used a chemical change involving gas or diesel fuel to make the vehicles run. Perhaps you cut a sandwich in half before eating your lunch; this was a physical change you created in the sandwich. 2. Using the Data able on the next page, record the physical and chemical changes in your environment. In the first column, record the change; in the second column, record your observations; and in the third column, state if the change is a physical change or a chemical change. ry to identify at least ten physical and chemical changes. he first one is done for you. Have fun! Data able (next page) Conclusion After completing the exercise, compile a class list of physical and chemical changes you observed. Discuss these observations as a class. Point out any errors in the list. Decide which changes are the most important, useful, and interesting.

9 6b Observing Changes in Your Environment Data able Change Observations Chemical or Physical Change? branch falling off tree branch made a cracking sound as it broke off main trunk of tree physical change

10 7 Writing Chemical Reactions We experience many chemical reactions everyday. A chemical reaction is a change in which two or more substances become new substances. Cooking our food often involves chemical changes, as does burning a candle or fire wood. We can observe chemical reactions by noting changes in color and/or temperature, the presence of bubbles, and the actual chemical change of a substance. Chemical reactions can be described in words and addition signs, the same addition signs you use in math to show that two numbers are added together. In a chemical reaction, the beginning compounds, or the reactants, that are present before the reaction occurs are written on the left side of the reaction. he new substances produced as a result of the reaction are written on the right side of the reaction. An arrow is written between the reactants and products. ollowing is an example of how to write the reaction between sodium and chlorine to produce sodium chloride (salt): sodium + chlorine sodium chloride Directions: Below are five chemical reactions. Describe the chemical reactions using words, addition signs, and arrows. 1. Photosynthesis involves plants taking in carbon dioxide, water, and the sun s energy to produce oxygen, water, and energy in the form of sugar. 2. When we breathe, we take in oxygen and water vapor, and give off carbon dioxide and water vapor. Directions: Using the information provided in the video, and hints from your teacher, symbolize the chemical reactions for the following, using words, addition signs, and arrows. 3. Symbolize the reaction of burning a piece of paper. 4. Symbolize the reaction of the rusting of a piece of iron. 5. Symbolize the he reaction that occurs between baking soda and vinegar.

11 8 Post - est Directions: ill in the blank with the correct word and or answer the questions if true or if false. Each question is worth 10 points. 1. Ice melting is an example of a change. 2. does not always stay the same, and can undergo physical and/ or chemical changes. 3. can play a large role in the physical change of matter. 4. In a chemical change, a substance if formed. 5. describes the ability of a substance to burn. 6. Heat is a clue that chemical change is occurring. 7. Rust is a substance produced by iron reacting with water. 8. Photosynthesis is a chemical reaction in green plants that produces energy and oxygen. 9. All chemical changes occur at the same speeds. 10. Every time you move, a chemical reaction occurs.