Indicators of chemical reactions Emission of light or

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Indicators of chemical reactions Emission of light or heat Formation of a gas Formation

Indicators of chemical reactions Emission of light or heat Formation of a gas Formation of a precipitate Color change Emission of odor

OBSERVING CHANGES OF MATTER • MATTER – Anything that has mass and takes up

OBSERVING CHANGES OF MATTER • MATTER – Anything that has mass and takes up space • CHEMISTRY –The study of matter and how it changes

T = Properties and Changes of Matter v. Properties of Matter ― Physical Property

T = Properties and Changes of Matter v. Properties of Matter ― Physical Property ―Characteristic of a substance that can be observed without changing the substance into another substance ―Examples – ―Melting point, color, Luster, texture, Hardness, flexibility

T = Properties and Changes of Matter v Properties of Matter ―Chemical Property ―Characteristics

T = Properties and Changes of Matter v Properties of Matter ―Chemical Property ―Characteristics of a substance that describes its ability to change into other substances. • Examples –Burning, Rusting, Tarnishing (patina)

Chemical Properties! IDEAS? • • Burning Burnt Marshmallow Bread to toast Cookies in the

Chemical Properties! IDEAS? • • Burning Burnt Marshmallow Bread to toast Cookies in the oven Firewood Grass fire ? Candle ? Definition? – React with Oxygen while heated! Rusting • • Bike frame Bike Chain Outdoor light fixtures Lawn furniture What RUSTS? ? HOW? anything with Iron (Fe) in it!! Reacts with oxygen in water! TARNISH? ? Metal + Oxygen or a Sulfide

T = Properties and Changes of Matter v. Changes of Matter ―Physical Change ―Consists

T = Properties and Changes of Matter v. Changes of Matter ―Physical Change ―Consists of any change which alters the appearance or form without changes is chemical makeup changing it into another substance. ―Examples ― change of state (solid, liquid, gas), shape, bending, crushing, cutting (iebraiding hair)

T = Properties and Changes of Matter v. Changes of Matter ―Chemical Change (chemical

T = Properties and Changes of Matter v. Changes of Matter ―Chemical Change (chemical reaction) ―Matter changing into a new substance ― examples, burning gasoline, burning magnesium, baking a cake

Student Activity - Classifying A. B. C. D. Piece of metal is heated until

Student Activity - Classifying A. B. C. D. Piece of metal is heated until it changes to a liquid Two clear solutions mixed. A yellow powder forms and settles to the bottom Water left in a dish overnight has disappeared by the next day A blacksmith hammers a piece of red-hot iron into the shape of knife blade. Physical Change Chemical Change

T = Properties and Changes of Matter v. Bonding and Chemical Change ―Chemical -

T = Properties and Changes of Matter v. Bonding and Chemical Change ―Chemical - changes occur when bonds break and new bonds from Review - ― Bonds made by sharing or transferring electrons (what types of bonds are these? ) Covalent vs Ionic O 2 (in air) + Mg metal

T = Evidence of Chemical Reactions v Changes in Properties ―Precipitate Solid from solution

T = Evidence of Chemical Reactions v Changes in Properties ―Precipitate Solid from solution ―Color Change ―Production of gas ―Change in moisture content ―Hardening ―

T = Evidence of Chemical Reactions v. Changes in Energy — Types - Heat,

T = Evidence of Chemical Reactions v. Changes in Energy — Types - Heat, light and electricity — Reaction - Absorption or release of energy ―Endothermic ― Absorption of energy (cold to touch) ―Exothermic ―Release of Energy (warm to touch)

Student Thoughts!! Exothermic Reactions (feels warm) Gives of Heat/Energy • Digestion • Burning Fuel

Student Thoughts!! Exothermic Reactions (feels warm) Gives of Heat/Energy • Digestion • Burning Fuel • Hand warmers Endothermic Reactions (feels cold) Absorbs Heat/Energy • Photosynthesis • Chemical cold pack

Assessment Questions •

Assessment Questions •

Writing a Conclusion – Power Outline • T = Hypothesis v What happened-the results

Writing a Conclusion – Power Outline • T = Hypothesis v What happened-the results § Details—Description § Details v Hypothesis right or wrong or somewhere in between. § Details- The why!!!! (Y) § Details v Conclude with thoughts of what was made! What are your results.

Conclusion Part 2 When the sugar is heated it will come together and harden

Conclusion Part 2 When the sugar is heated it will come together and harden because it was a chemical change. When the sugar was heated it melted and turned brown then hardened. The sugar emitted a sweet scent. It turned a little translucent and slightly amber in hue. While it smelled sweet it also smelled slightly bitter. Our hypothesis was partially correct. The sugar turned hard but we did not think about the color change. We also did not anticipate the change in the fumes of the sugar. As the sugar was heated it carmalized and thickened.

Power Outline – 5 th Period • T= Hypothesis v The Results –What Happened-What

Power Outline – 5 th Period • T= Hypothesis v The Results –What Happened-What it saw § Details –Description § Details v Hypothesis- Right, Wrong, Somewhere in between § Details – what was right § What was wrong § What was missed v Propose product – what do you think the results or products is/are? § Details – why? Your reasoning.

Conclusion Part 2 (P 5) If we heat the sugar, the sugar would melt

Conclusion Part 2 (P 5) If we heat the sugar, the sugar would melt because of the chemical reaction. Our lab results showed a change of color and precipitation. The sugar hardened and turned brown. It also bubbled. The aluminum turned black and candle wax melted. It smelled like the taste of a smore. Our hypothesis was correct regarding a physical change. However, it hardened, changed color and had a different smell. There was a chemical change because of the change color and smell and hardness of the browned sugar. We conclude that the sugar carmalized.

Skills Lab • Where is the Evidence? • PRELAB in Class. Fill out lab

Skills Lab • Where is the Evidence? • PRELAB in Class. Fill out lab worksheet. Problem. Materials, Procedure, and table preparations. • Lab – write the procedure as it is accomplished. Write down all observations in the table. • Answer questions 1 -7 • Formulate a conclusion for the lab.