How can we classify change?

What things changed in Monday’s lab?

Which did not change?

Physical Change

• Changes that can be reversed are called Physical Changes

• Our experiments with mixtures and solutions were all physical changes – we could use the techniques of separation of mixtures to reverse them.

• Remember the changes of state: melting, evaporation, freezing, etc? Do you think they are examples of physical change?

• YES!

Examples of Physical Change

• Evaporation, Condensation, Melting, Freezing, Sublimation, Deposition

• Chopping, crushing or breaking something • Bending or reforming stuff• Mixing stuff up• Absorption• What 2 physical

changes are represented by this picture?

What about changes that can’t be reversed?

• Take 3 minutes to discuss with the student behind or in front of you what are some examples of changes that cannot be reversed. Write down what you come up with.

• Let’s share!

• Changes that cannot be reversed are called Chemical Change

Chemical Change

• Chemical change happens when a new substance is formed during the change. When this happens, the original substances cannot easily gotten back

• With the same partner, brainstorm ways in which new substances are formed. You have 3 minutes.

• Let’s share!

Examples of Chemical Change

What are the processes behind some of those chemical changes?

• Burning• Eating• Breathing (and Photosynthesis)• Rust (oxidation)• Rotting• Also, certain chemicals can react when they

combine to make a new substance• For example, acids and bases react to make salt

Bibliography of Images• http://4.bp.blogspot.com/_kC5MT2r5U8s/TIdMBXtBxXI/AAAAAAAAQiw/HP_nuuh0tzs/s1600/GOP+red+kool+aid.j

pg• http://t3.gstatic.com/images?q=tbn:ANd9GcQGpDrNQKXPF5e_y6oMi7gNy1BcIEnpUgPYE1BKyaL4UV6vG_o&t=

1&usg=__7aMba67ItG7ux-UfxyRRA-6s06w=

• http://ic2.pbase.com/o6/49/99249/1/70982707.xwHQllgm.OilonwaterNov30.2.jpg• http://www.pollsb.com/photos/o/38393-crushed_ice.jpg• http://news.pillaicenter.com/wp-content/uploads/2010/07/fire1.jpg• http://www.edb.utexas.edu/petrosino/Legacy_Cycle/mf_jm/Challenge2/images/breathing.gif• http://magickcanoe.com/history/rust-fence-tractor-large.jpg• http://blog.ecosmart.com/wp-content/300px-rotting_fruit.jpg• http://upload.wikimedia.org/wikipedia/commons/0/02/Fried_egg,_sunny_side_up.jpg