1. CHEMICAL & PHYSICAL CHANGES
CHAPTER 3
CHEMICAL & PHYSICAL CHANGES

2. MATTER IS ANYTHING THAT HAS MASS AND TAKES UP SPACE 2 CATAGORIES:
PURE SUBSTNCES
MIXTURES

3. PURE SUBSTANCES ARE MADE UP OF ONLY ONE KIND OF MATERIAL
TABLE SALT (NaCl)
GOLD
IRON
ELEMENTS ARE THE SIMPLEST TYPE OF SUBSTANCE (reference metal/ non-metal)

4. COMPOUNDS IS MADE UP OF TWO OR MORE ELEMENTS
THAT ARE CHEMICALLY ATTACHED TO EACH OTHER
WATER & SUGAR ARE EXAMPLES
ORGANIC COMPOUNDS CONTAIN:
HYDROGEN
OXYGEN
NITROGEN
SULFUR

5. MIXTURES
ARE TWO OR MORE SUBSTANCES THAT HAVE BEEN SIMPLY COMBINED-NOT CHEMICALLY- oil & vinegar
HETEROGENEOUS MIXTURES: are recognized by site ( salad=carrots, lettuce)
HOMOGENEOUS MIXTURES: is the same in every part of a given sample (pancake syrup)
Solution 1 is dissolved in another

6. CHEMICAL CHANGES
IS A CHEMICAL CHANGE WHEN A SUBSTANCE BECOMES A NEW SUBSTANCE AND DIFFERENT SUBSTANCES
SOME CHEMICAL CHANGES CAN RE REVERSED-THE PHOTOSYTHESIS PROCESS
SOME CHEMICAL CANNOT BE REVERSED- BURNING TOAST, HOT DOGS,ETC

7. PHASE CHANGES
SOLID – ICE
LIQUID – WATER
GAS – STEAM

8. CHANGES IN FOOD
CHANGES TAKE PLACE IN FOOD DURNING COOKING AER BOTH PHYSICAL AND CHEMICAL