8.5 The student knows that matter is composed of atoms and has chemical and physical properties. 8.5D that chemical formulas are used to identify substances and determine the number of atoms of each element in chemical formulas containing subscripts. CHEMICAL FORMULAS USES GRADE 8 Unit 04: Chemical Formulas, Equations and Reactions 2010 TEKS 1998 TEKS Curriculum and Instruction Considerations 8.8 The student knows that matter is composed of atoms. identify substances determine the number of atoms of each element VII. Chemistry H2 Understand energy changes and chemical s. 8.9C the importance of formulas and equations to express what happens in a chemical. IMPORTANCE OF FORMULAS AND EQUATIONS IN REPRESENTING CHEMICAL REACTIONS law of conservation of mass Note: Students understand that chemical s represent the rearrangement of elements. Students are NOT required to balance equations. 7.7A Identify and demonstrate everyday examples of chemical phenomena such as rusting and tarnishing of metals and burning of wood. Identify, EXAMPLES OF CHEMICAL PHENOMENA Use 8 th grade, Unit 3 Lesson 1 Engage Use page 3 Omit -It s in the Bag Part A & B pages 4-5. Omit or modify page 5. Teacher may want to describe what exothermic and endothermic mean. Do You Lose Anything page 6 Counting Atoms page 6 Law of Conservation of Mass pages 6-7 Use this site for further practice on balancing equations: http://www.sciencespot.net/media/blncact.pdf I Have Who Has page 7. The cards (pages 30 & 31) will have a reference to endothermic and exothermic. Give students those answers to students if that section was omitted. Evaluate Omit pages 8 &32 Performance Indicator 2010, TESCCC 08/03/10 page 1 of 5
8.5F whether a chemical equation containing coefficients is balanced or not and how that relates to the law of conservation of mass. WHETHER A CHEMICAL EQUATION CONTAINING COEFFICIENTS IS BALANCED relationship to the law of conservation of rusting and tarnishing of metals (oxidation) burning of wood corrosion 8.9A that substances may react chemically to form new substances. SUBSTANCES MAY REACT TO CHEMICALLY FORM NEW SUBSTANCES change: energy change change new substance produced precipitate formation release of a gas 8.9C the importance of formulas and equations to express what happens in a chemical. IMPORTANCE OF FORMULAS AND EQUATIONS IN REPRESENTING CHEMICAL REACTIONS 2010, TESCCC 08/03/10 page 2 of 5
mass law of conservation of mass Note: Students understand that chemical s represent the rearrangement of elements. Students are NOT required to balance equations. 8.9D Identify that physical and chemical properties influence the development and application of everyday materials such as cooking surfaces, insulation, adhesives, and plastics. Identify EVERYDAY APPLICATIONS OF PHYSICAL AND CHEMICAL PROPERTIES physical properties porosity hardness conductivity solubility density viscosity luster chemical properties reactivity corrosiveness flammability oxidation application cooking surfaces insulation adhesives 2010, TESCCC 08/03/10 page 3 of 5
8.5 The student knows that matter is composed of atoms and has chemical and physical properties. 8.5E Investigate how evidence of chemical s indicates that new substances with different properties are formed. Investigate HOW EVIDENCE OF CHEMICAL REACTIONS INDICATES THAT NEW SUBSTANCES ARE FORMED change ion of a gas change in temperature ion of a precipitate compare differences in properties between products and reactants VII. Chemistry E1 Classify chemical s by type. Describe the evidence that a chemical has occurred. VII. Chemistry H2 Understand energy changes and chemical s. plastics 8.8 The student knows that matter is composed of atoms. 6.7A that new substances can be made when two or more substances are chemically combined and compare the properties of the new substances to the original substances. HOW NEW SUBSTANCES WITH DIFFERENT PROPERTIES EMERGE FROM A CHEMICAL REACTIONS evidence of a chemical release of gas release of light/heat temperature change compare differences between products and reactants 7.7A Identify and demonstrate everyday examples of chemical phenomena such as rusting and tarnishing of metals and burning of wood. Identify, Concept moved from Grade 7. Similar concept found in Grade 6. Use 7th grade, Unit 10 Lesson 1 Omit Evaluation Use 6th grade Unit 1 Lesson 2 Use page 6 Use page 7 Elaborate Stations 3 & 4 only pages 8-9, 14 & 15. Evaluate Performance Indicator 2010, TESCCC 08/03/10 page 4 of 5
EXAMPLES OF CHEMICAL PHENOMENA rusting and tarnishing of metals (oxidation) burning of wood corrosion 8.9A that substances may react chemically to form new substances. SUBSTANCES MAY REACT TO CHEMICALLY FORM NEW SUBSTANCES change: energy change change new substance produced precipitate formation release of a gas 2010, TESCCC 08/03/10 page 5 of 5