Warm Up 33 Complete the mini worksheet at your seat DateSession # ActivityPage # 10/8-9 13Chemical Change Lab31 Chemical Properties and Change Notes32 10/ Precipitate and pH Investigations33 Chemical Change Quick Write34 Homework: Read 69D-72D and 86D-91D Answer ?’s: 1-2 on 76D 1-6 on 91D 5, 11,19-21 on 102D

Warm Up p. 33

Notebook Check formal grade 10/19 P7 ion/isotope text talk P 13, Periodic table LINK P19 periodic table blendspace P25 physical properties stations P31 chemical change lab

8.P.1 Understand the physical properties of matter and changes that occur when matter interacts in an open or closed container 8.P.1.3 Compare physical changes such as size, shape and change of state to chemical changes that are a result of a chemical reaction to include changes in temperature, color, gas or formation of a precipitate.

Objective TLW explain chemical changes by observing and making connections for several experimental trials then complete a quick write.

Notes Chemical change: a change that occurs that causes the chemical makeup (composition) of a substance to change. Chemical bonds are broken and new ones created Evidence – Color change – Gas produced -- Precipitate – Temperature change (Exothermic & Endothermic) – Light produced/flame/smoke Examples: rusting, burning/combustion A chemical change is also called a chemical reaction

Notes (there’s more..) Some chemical changes release energy…heat, light, etc. They get warmer. These are EXOTHERMIC Some chemical changes absorb energy…they get colder. These are ENDOTHERMIC Go back to your lab results. Note if the reaction was endothermic or exothermic. Not all reactions are endothermic or exothermic.

Chemical Property Properties that change the chemical nature of matter….chemical properties can only be observed or measured in a chemical reaction P 32

Chemical Properties (add to notesheet) pH Reactivity Combustion/flammability Tarnish Corrosion Rusting

pH A measurement of how acidic (1-6) or basic (8-14) a material is

Reactivity How easily a substance reacts with other substances. (how easily it undergoes a chemical change) B4 B4

Combustion/flammability Rapid reaction with oxygen, produces heat & light Reactant + Oxygen ----> Oxide(s) + heat + light

Corrosion The gradual destruction of materials (usually metals) by chemical reaction with their environment.

Rusting Creation of Iron oxide. Iron forms Iron oxide (rust) when iron reacts with oxygen and water.

Tarnish A thin layer of corrosion that forms over some metals. It only affects the outermost layer of the material. Unlike rust, the layer of tarnish seals and protects the underlying layers from reacting. Silver tarnish Copper tarnish

Chemical Property Investigations…Unknown Substance What gas was produced in each of these investigations? What chemical properties of the gas can we use to determine its identity? 3NaHCO 3 + C 6 H 8 O 7 + H 2 O  ? (baking soda) (citric acid) Catalase (Enzyme produced by yeast) H 2 O 2 ? CH 3 COOH + NaHCO 3  ? (vinegar) (baking soda)

Chemical Property Investigations…Unknown Substance What gas was produced in each of these investigations? What chemical properties of the gas can we use to determine its identity? 3NaHCO 3 + C 6 H 8 O 7 + H 2 O  3NaC 6 H 5 O 7 + 3H 2 O + 3CO 2 (baking soda) (citric acid) Catalase (Enzyme produced by yeast) H 2 O 2 H 2 O + O 2 CH 3 COOH + NaHCO 3  NaC 2 H 3 O 2 + CO 2 + H 2 O (vinegar) (baking soda)

Quick Write p 34 Compare physical changes to chemical changes. Make sure you define each. Cite evidence from the physical changes you saw in the stations and the chemical changes you saw in the lab to support your answer.