Name. Readiness Standard 8.5E. After this lesson I will be able to:

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1 motivationsiene STUENT EITION The Motivation Science Student Edition contains a unit for each of the tested standards, and includes 40% or greater questions that are dual-coded to the content standard and Scientific Investigation and Reasoning Skills. or every content standard, the Motivation Science Student Edition includes introduction investigations to engage students, guided practice questions, check for understanding questions, critical thinking/journal activities, homework/parent connections, and reporting category assessments. Motivation Station: Scientific act Unit 5 Introduction ireworks are elaborate chemical reactions crafted to explode with vibrant colors and patterns. irework reactions give evidence of chemical reactions by sound, light, color, odor, and temperature. this lesson I will be able to: Investigate how evidence of chemical reactions indicate that new substances with different properties are formed. Experimental Investigations Activity 1: Investigating Evidence of hemical Reactions Procedure 1. Obtain a resealable plastic bag for each chemical reaction. Label the resealable plastic bags 1 through Measure temperature and observe color and state of matter for each chemical. Record observations below. 3. ollow the reaction procedures below. Reaction 1 Reaction 2 Place a portion cup containing 25 g of ammonium nitrate in a plastic bag containing 50 ml of water. Remove air from the bag and seal closed. Turn the bag over and knead the mixture. Reaction 3 Reaction 4 Pour 50 ml of copper sulfate solution into the plastic bag and add an iron nail. Remove air from the bag and seal closed. Place a portion cup containing 50 g of baking soda in a plastic bag containing 50 ml of vinegar. Remove air from the bag and seal closed. Turn the bag over and knead the mixture. Pour 10 ml of bromothymol blue solution into the plastic bag. Insert a straw and seal the bag around the straw. low carbon dioxide gently for 1 minute. 4. uring each chemical reaction, observe temperature, color, and states of matter of the substances formed. 5. ased on your observations, determine the evidence of reaction for each investigation. Reaction hemical efore Reaction Reaction Evidence of Reaction 1 Ammonium nitrate Water 2 aking soda Vinegar 3 opper sulfate Iron nail 4 romothymol blue arbon dioxide o all chemical reactions have the same evidence for chemical reactions? Explain your answer. o the substances created during the chemical reactions have the same properties as the original substances? 2012 mentoringminds.com motivationscience LEVEL 8 illegal to copy 45 introduction 16 mentoringminds.com/staar-resources

2 motivationsiene Unit 5 Introduction Activity 2: Simulating Real-Life hemical Reactions Investigate the following chemical reactions and record all observations (temperature change, color change, gas formation, etc.) in the table below. Relate each chemical reaction to a real-life example in which similar evidence of chemical reaction applies. Procedure Simulation 1 1. Place a Wintergreen Life Savers candy inside the jaws of a pair of pliers. 2. arken the area of the room where the experiment will be conducted. 3. rush the Life Savers candy with the pliers. Simulation 2 1. Place 100 ml of vinegar in a plastic cup. 2. Test the p of the vinegar. 3. rush an antacid tablet and pour into the vinegar. 4. Stir the mixture with a spoon. 5. Test the solution after reaction with p paper. Simulation 3 1. Place 60 ml of warm water (38 43 o ), 5 grams of sugar, and 1 active dry yeast packet in a clear plastic cup. 2. Stir the mixture with a spoon. 3. Let mixture stand for 10 minutes. efore: : efore: : efore: : Observations Evidence of Reaction Real-Life Example All materials should be disposed of in appropriate containers designated by the teacher at the end of the investigation. RAE LEVEL 8 student edition When a chemical reaction occurs, will more than one chemical reaction indicator occur? Why or why not? Are new substances created during these chemical reactions? ustify your answer. Why do some chemical reactions occur immediately and others occur over time? 46 illegal to copy motivationscience LEVEL mentoringminds.com introduction mentoringminds.com/staar-resources 17

3 motivationsiene RAE LEVEL 8 student edition 1 elow is an example of a model used to represent a chemical equation. ow does this model assist a student in providing evidence a chemical reaction has occurred? (8.3) A The student can use the different colored dots to show no new substance was created from the original molecules. The student can use the different colored dots to show a new substance was created from the original molecules. This model does not show that a chemical reaction occurred. The student can use the different colored dots to show a new element was formed from the original elements. 2 A student mixes two liquids together and notices that a white solid has formed at the bottom of the container. What can the student conclude? (8.2E) 1. A precipitate has formed. 2. A physical change has occurred. 3. A chemical reaction has occurred. 4. A chemical change has occurred. 1 and 2 only 1, 2, and 4 only 1, 3, and 4 only 3 only 3 Two chemicals are mixed and sealed in a plastic bag. The bag begins to inflate and becomes hot to the touch. What evidence can the student cite to show a chemical reaction occurred? A ormation of a gas Increase in temperature ormation of a gas and increase in temperature No chemical reaction 2012 mentoringminds.com motivationscience LEVEL 8 illegal to copy 47 2 roups of students complete several stations to mix substances. They wonder if the chemical reactions formed new substances. Which of the following questions would be most appropriate to ask? as a physical change taken place? as a chemical reaction altered the substances properties? as mass been destroyed or created? What will happen when each substance melts? check for understanding Unit 5 uided Practice 4 A group of students mixed 20 ml of white glue and 20 ml of water in a cup. Three drops of food coloring were added to the mixture. Then, 15 ml of borax solution was stirred into the mixture. Once mixed, the students observed they could take the substance out of the cup, roll it around in their hands, and play with it. The students concluded (8.2E) the white glue was the precipitate of the chemical reaction a new substance was formed indicating a physical change only the new substance formed was a gas a precipitate was formed indicating a chemical change 5 Students X and Y mix two clear liquids together during a laboratory investigation. They notice the color of the new solution is red. Student X concludes there has been a chemical reaction. Student Y concludes there has not been a chemical reaction. Which student drew a valid conclusion based on the information provided? (8.3A) A Student X is correct because when two liquids are poured together there is a chemical reaction. Student Y is correct because color is a physical property, not a chemical property. Student X is correct because a change in color is evidence of a chemical reaction. Student Y is correct because there must be bubbling if there is a chemical reaction. 6 Which description provides evidence that chemical reactions form new substances with different chemical properties? ubbles formed in a bathtub ood coloring added to water utter being melted in a pan Eggs being fried in a skillet Unit 5 heck for Understanding guided practice 1 Which statement is not evidence that a new substance has formed during a chemical reaction? A as is produced. Temperature changes. Precipitate forms. Substance melts. 3 uring an investigation, students mixed an unknown powder and unknown liquid. When the students poured the liquid into the powder, bubbles were produced. Which statement correctly identifies the type of investigation? A The powder and liquid repelled one another and produced bubbles. The powder and liquid produced bubbles because the law of conservation of mass was violated. The powder and liquid produced bubbles because a chemical reaction occurred. The powder and liquid produced bubbles because a physical change occurred. 4 The chemical reaction shown below involves the reaction of silver nitrate with potassium chloride. AgNO 3 Kl Agl KNO 3 Liquid Liquid Solid Liquid 5 Photosynthesis is a process that occurs in all plants. Which statement is true concerning photosynthesis? A Plants take in carbon dioxide and water to make new substances, glucose and oxygen, by a process called photosynthesis. Plants give off light as a result of the chemical reactions in photosynthesis. Plants change from green to brown as a result of the chemical reactions in photosynthesis. Photosynthesis is not a chemical reaction but a physical change in plants. 6 Which investigation results do not represent evidence of a chemical reaction? efore efore efore efore What evidence of chemical reaction will be observed based on this chemical reaction? as formation lash of light ecrease in mass ormation of precipitate illegal to copy motivationscience LEVEL mentoringminds.com 18 mentoringminds.com/staar-resources

4 USA motivationsiene check for understanding Unit 5 heck for Understanding 11 ombustion is a process in which fuel, oxygen, and heat react to produce large amounts of energy. This process was discovered in the 1600s and is still used today for a majority of energy on Earth. The space shuttle uses the fuel hydrogen gas to propel itself into outer space. 13 Two students recorded temperature values in science notebooks during a laboratory investigation. rom the recorded data, students created the following graph. Temperature ( ) Y Time (minutes) Unit 5 heck for Understanding Scientific Investigation and Reasoning Skills: Questions Students conduct two experiments to determine if a chemical reaction has taken place. Test Tube ontents lue food coloring and water lue food coloring, water, and bleach Observations lue solution lear solution Students conclude from the data that the first experiment demonstrates a physical change, while the second experiment demonstrates a chemical reaction. What evidence best supports the conclusion? (8.2E) A No new substance was made with the mixture of food coloring and water. A new substance was made with the mixture of food coloring and water. Neither mixture is an example of a chemical reaction. oth mixtures are examples of chemical reactions. 8 A teacher wants to show his students a chemical reaction involving highly explosive hydrogen gas and oxygen gas. Which of the following is the best way for the teacher to proceed? (8.1A) Perform a demonstration of the reaction using a student volunteer instead of allowing the students to conduct the experiment themselves Show the students a video clip of the reaction to avoid potential explosions Allow the students to complete the experiment under close supervision and only after a very detailed lab safety briefing Ask another teacher to come in and help monitor the students during the experiment 9 Two students complete an investigation in which they observe several chemical reactions. Some observations before and after the reactions are recorded below. Reaction A Reaction efore the Reaction Two clear liquids Temperature of 20 the Reaction A clear liquid and a white solid Temperature of 55 Reaction Two gases One liquid Which question did the students most likely investigate? (8.2) 2012 mentoringminds.com motivationscience LEVEL 8 illegal to copy 49 X A Are the properties of substances the same before and after a chemical reaction? What are indicators of a physical change? ow do properties change before a chemical reaction? What are chemical properties? 10 Students will perform a series of chemical reactions in order to identify which reactions are exothermic (show an increase in temperature) or endothermic (show a decrease in temperature). Which tool is appropriate to use when conducting this investigation? (8.2A) Spectrometer ire blanket Thermometer ot plate RAE LEVEL 8 student edition What evidence of a chemical reaction does the space shuttle exhibit? (8.3) A ormation of precipitate Emission of light isintegration of the element hange of color 12 Two students investigate chemical reactions of three unknown liquids. Which of the following is the best experimental design? (8.2) 1. Place the same amount of baking soda in 2. Pour a different amount of each liquid into each test tube. 1. Place the same amount of baking soda in 2. Pour a different amount of each liquid in the same test tube. 1. Place a different amount of baking soda in 2. Pour a different amount of each liquid in each test tube. 1. Place the same amount of baking soda in 2. Pour the same amount of each liquid in the appropriate test tubes. What can the students conclude based on this information? (8.2E) A A decrease in temperature is evidence that a chemical change has occurred. An increase in temperature is evidence that a chemical change has occurred. A decrease in temperature is evidence that a physical change has occurred. An increase in temperature is evidence that a physical and chemical change have occurred. 14 A student conducting a chemical reaction hypothesizes that a clear liquid mixed with a colored solid will form a clear liquid with properties similar to the original liquid. Is this a valid hypothesis statement? (8.3A) Yes, because the new substance formed in the chemical reaction will have properties similar to the original liquid. No, because the new substance formed in the chemical reaction will have properties similar to both substances used in the reaction. No, because the new substance formed in the chemical reaction will have properties similar to the original solid. No, because the new substance will have properties different from both original substances. check for understanding 50 illegal to copy motivationscience LEVEL mentoringminds.com mentoringminds.com/staar-resources 19

5 motivationsiene RAE LEVEL 8 student edition Synthesis Identify Substances by hemical Reactions Unit 5 ritical Thinking Imagine you are given four white powders that consist of sugar, salt, baking soda, and cornstarch. Your investigation will identify the substances based on evidence of chemical reactions. Use the materials listed to create an investigative plan for identifying the unknown substances. Plan your investigation below. Materials test tubes balance graduated cylinder spoon stirring stick vinegar water iodine solution heat source sugar salt baking soda cornstarch Investigative Procedure the investigation is complete, how will you identify the four white powders? What evidence will support your conclusions? Unit 5 ournal Science ournal A new and improved cleaner is advertised by the manufacturer. The advertisement claims a new chemical reaction has been discovered that will clean dirt and grease in seconds. What evidence should the manufacturer provide to back up its claim? Support your answer mentoringminds.com motivationscience LEVEL 8 illegal to copy 51 critical thinking NEW and IMPROVE journal 52 illegal to copy motivationscience LEVEL mentoringminds.com 20 mentoringminds.com/staar-resources

6 motivationsiene Unit 5 omework hemical Reactions at ome hemical reactions happen all around us. Some examples of common chemical reactions are listed below. omplete the following chart based on your knowledge of science and evidence of chemical reactions. hemical Reaction vocabulary activity escription of substances before the chemical reaction escription of substances after the chemical reaction Evidence that a chemical reaction occurred Science Vocabulary uilder Unit 5 Vocabulary Activity omplete the graphic organizer below with illustrations of the evidences of chemical reactions. Light Te m perature hange as ormation Evidences of hemical Reactions Sound olor hange Precipitate 2012 mentoringminds.com motivationscience LEVEL 8 illegal to copy 53 RAE LEVEL 8 student edition ooked egg aked cake Leaves changing color homework Wood burning Rusting nail Parent Activities 1. iscuss with your child what each of the substances look like before and after chemical reactions. What indicates that a chemical reaction occurred? 2. rainstorm other real-life examples of chemical reactions. What do they have in common with the chemical reactions above? 3. reate your own chemical reaction to test at home. Remember, safety is very important. 54 illegal to copy motivationscience LEVEL mentoringminds.com mentoringminds.com/staar-resources 21