a. Students know how to describe chemical reactions by writing balanced equations.

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1 Learning Sequence: Chemical Reactions and Law of Conservation of Mass This is a 5-day instructional module embedded into a larger sequence of modules and lessons that allow for the learning and reinforcement of the Law of Conservation of Mass (see diagram at the end of this document). The specific Common Core State Standards addressed during key elements of the learning sequence are indicated in square brackets. The Law of Conservation of Mass states that mass cannot be created or destroyed. This means that the total mass of reactants in a chemical reaction will equal the total mass of the products. Mathematically this is represented by the appropriate balancing of chemical equations, regardless the type of chemical reaction involved in the process. S: Students DSJ: Daily Science Journal T: Teacher DSR: Daily Science Reflection Science Standard Chemistry grades 9-12 and Modulespecific Concepts At home activity Day 1 Day 2 Day 3 Day 4 Day 5 3. The conservation of atoms in chemical reactions leads to the principle of conservation of matter and the ability to calculate the mass of products and reactants. a. Students know how to describe chemical reactions by writing balanced equations. S read assigned textbook sections and write Cornell notes for the content that will be addressed during the [RST ; RST ; RST ; RST ] S complete assigned practices S read pre-laboratory handout and prepare written pre-lab notes in their notebook [RST ; RST ; RST ; RST ] [WHST ] S respond in writing in their notebook to 5 prompt questions related to the lab activity by using textbook and notebook. Start thinking about possible conclusion statements. [RST ; RST ] S complete the report on their lab experience, including the conclusion (CCR) section, a reflection on the formulated hypothesis, and a qualitative analysis of the sources of errors associated with the lab. Beginning/ Engage S write DSJ notebook entry: a prompt question is projected on the screen related to key ideas from the materials presented S T [WHST ; S T [WHST ] S check their notebooks with T to verify their readiness to conduct the experiments. If ok, they can put on safety lab [RST ] [WHST ; WHST WHST.9- S complete a weekly study sheet summarizing all the key concepts addressed during the

2 during this unit that highlight student s understanding and prior knowledge. T checks homeworks, daily planner entry, and ask specific questions to S individually regarding content from the previous T demonstrates single replacement chemical reaction with aluminum into a solution of copper chlorite. T guides S in classroom discussion to determine what is causing the aluminum to transform from a silver substance into a reddish substance. WHST.9- T demonstrates combustion reaction by burning magnesium. T guides S to review their notes in order to answer questions related to combustion reaction. [RST ; RST ] 10.4; gowns and check at their assigned station. T check completeness of multistep procedure to conduct the experiment, verify attention to safety rules, assign S to lab station. Without the aid of their notebooks, S write a summative report of all they have learned during the The section should contain as many sentences as possible; each sentence must contain and introduction, a supporting evidential statement, and a conclusion. [WHST ; WHST.9- T works with S to determine the proper chemical equation associated with the demonstration and balance it. L.9- Middle T assigns in sequence several chemical equations to be balanced with increasing level of difficulties. Mastery of academic language is T engages S in comparing and contrasting organic versus inorganic chemical combustion and the T review pre-laboratory handout and assigns 5 questions that must be completed before starting the lab. The questions allow S conduct a laboratory experimentation in which they identify 5 different types of chemical reaction. S are assigned a weekly quiz to assess content knowledge.

3 emphasized. S solve equations by using their notebook, the table of the elements, charts, and white boards; they are prompted to help each other in reaching a solution. L.9- T introduces new material using direct instruction. The new material relates to the 5 types of chemical reactions. S review their Cornell notes by highlighting key concepts and adding missing information. L.9- relevance of this knowledge for firefighters. 10.4; students to focus on specific key observations they will have to record in order to identify correctly 5 different chemical reactions. 1) How does a decomposition reaction differ from other types of reactions? 2) In a combustion reaction, what products form in addition to any new compound? 3) Which two ions should be used in very small quantities because they are toxic and bioaccumulative, that is, they build up in body tissues? 4) During which steps of the procedure would you expect to produce gas? 5) What safety precaution applies when heating a test tube? By using their notebooks, S: 1) Gather materials for experiment. 2) Follow procedures to achieve a chemical reaction 3) Collect observations in the data table in their notebooks 4) Reason on evidence to formulate a claim regarding the type of chemical reaction After all chemical reactions are completed, S in teams bring their notebook with data and conclusions to T for verification. [RST ; RST ] [WHST ; WHST ; WHST ; WHST ] T help S to answer the questions by allowing them to review their notebook entries and their chemistry charts (ionization and oxidation, and the table of the elements) S review the materials needed, check the

4 necessary safety precautions associated with the experiment, and develop a series of hypothesis associated with each described reaction based on their knowledge and by reviewing their notebook entries. [RST ; RST ; RST ; RST ] 10.4; WHST ] T assesses S by asking them to summarize their learning from the day and ask them how does it connect to the principle conservation of matter. 10.4; S clean up lab stations, dispose chemical materials as appropriate, wash chemical tools and materials and return them to stock table. Conclusion S write DSR entry in notebooks while T checks Cornell notes and ask questions to each student individually differentiating by level of mastery of the subject matter. L.9- S write the Classroom Closure and Relevance section in their notebook. The CCR is a conclusion section at the end of each lab experience in which S describe how the laboratory experience was connected to the learning during the week and how the experience may be relevant to their daily lives. [WHST ]

5 Overview of chemistry concepts associated with the principle of conservation of matter CONVERT MOLAR MASS to moles, # of particles and volume of gases at STP 1 MOLE = 6.02 x particles DETERMINING MOLAR MASS CALCULATE MASS OF REACTANTS AND PRODUCTS LAW OF CONSERVATION OF MATTER (Chemistry, 3a-g) DEFINING THE MOLE (1 mole of C 12 =12g) CALCULATE % YIELD WRITING BALANCED CHEMICAL EQUATIONS REDOX RXNS Identify and balance