Warm-up  Explain what is wrong with the following equation. H O H 2 O Reactant Product

Key Question Burning an envelope is a ________ change because something new is formed. **physical **chemical Physical and Chemical Changes

Student Objective Tuesday, February 23, 2016 OBJECTIVE:  SWBAT will identify that a new substance is formed during a chemical change. HOMEWORK: Physical and Chemical Changes

Agenda  Discuss the warm up  Read the key question for the focus of today’s lesson  Lab: Physical or Chemical Change  Slides: What the difference between a physical and chemical change?  Interactives: Physical and Chemical Changes

REVIEW: View the interactive site below– “the formation of water”. What does it show about the number of atoms you begin with compared to the number of atoms you end with?.  Click on “The formation of water” rary/module_viewer.php?mid=56 rary/module_viewer.php?mid=56

Physical or Chemical Change Lab  Follow the directions on your worksheet.

 Matter can undergo two kinds of changes…. PHYSICAL changes and CHEMICAL changes.

Physical Change a change that affects the appearance of a material but does not make a new substance. Differences between chemical and physical changes… Chemical Change a change that forms one or more new substances. Add these words and meanings to your vocabulary. Illustrations

Examples of Physical Changes….Why? tearing paper chopping wood molding clay melting ice

Chemical changes are changes in matter that produce one or more new substances. For example, when you burn a log in a fireplace, you are carrying out a chemical change that changes the wood to ashes. Other examples of chemical changes are:

Digestion: Once it is digested, it is not bread anymore!

Photosynthesis: A plant changes sunlight, carbon dioxide and water into sugar. Thisis a chemical change. Sugar…a new substance is formed!

Burning: Wood changes to ash New substance!

Decomposition: Fruit changes to rotten matter There is no way I’m eating that…It isn’t an apple anymore!

raw egg becomes cooked egg cake mix becomes cake paper becomes ash steel becomes rust Discuss with your group why each of these is a “chemical change”.

Think about why this a chemical change? Click on the picture below to see another chemical change. BURNING CANDLE

Go to these 2 websites to practice identifying physical and chemical changes

Interactive Activities Physical Changes …Chemical Changes? Click here!

 Introduction to “indicators”….Read the information on this slide to learn about the indicators of chemical changes Fill out the “Main Idea” graphic organizer.  Compare and contract physical and chemical changes….Read the information and then do the TEST BYTE ry/classifyingmaterials/elements_and_compoundsre v3.shtml ry/classifyingmaterials/elements_and_compoundsre v3.shtml

Review Chemical and Physical Changes  Review indicators of chemical and physical changes 06/physicalchemicalchangews.htm 06/physicalchemicalchangews.htm  Answer the questions on this site. Put your answers in your notes. cass.org/site/post_primary/science/downloads/powerpoints/Physical%20and %20Chemical%20Change.pps cass.org/site/post_primary/science/downloads/powerpoints/Physical%20and %20Chemical%20Change.pps  Then complete Summary Quiz – Chemical Changes, Physical Changes, Indicators WS

Conclusions:  In your note section, draw and explain an example of a physical change and a chemical change.