1. Do Now… 1- Copy the HW 2- List as many elements as you can
Do Now… 1- Copy the HW 2- List as many elements as you can (without looking at a periodic table)
HOMEWORK –
Read 2.5
#’s 13-15
Element Flashcards for Fri (1-36)
EC=Personal Element Poster

2. ELEMENTS
Element – a substance that cannot be broken down into other substances by chemical methods.
the simplest form of matter that has a unique set of properties.
examples – gold, neon, copper, astatine, carbon, bromine…

3. EVERYTHING ON THE PERIODIC TABLE IS AN ELEMENT!!!

4. COMPOUNDS
Compound – a substance composed of a given combination of elements that can be broken down into those elements by chemical methods
ALWAYS contains DIFFERENT elements
examples – magnesium oxide (MgO), water (H2O), sodium chloride (NaCl)…

5. Breaking Down Compounds
Compounds can be broken down into simpler substances by chemical methods, but elements cannot.
Ex: When sugar is heated,it goes through a chemical change.

6. Breaking Down Compounds
Final products = carbon and water vapor
Can then break down H2O into H2 and O2 using electricity

7. Properties of Compounds
In general, the properties of compounds are quite different from those of their component elements.
chlorine (Cl2)is used to kill harmful organisms in swimming pools.
sodium vapor (Na) produces the light in some street lamps.
sodium chloride (NaCl), commonly called salt, is used to season or preserve food.

8. Mixtures & Pure Substances
How can pure substances and mixtures be distinguished?
A mixture has a variable composition.
Must be a mixture of compounds and/or elements.
Ex: air, granite, chicken noodle soup
A pure substance ALWAYS has the same composition.
Must be an element or a compound.
Ex: water, silver

9. TYPES OF MIXTURES HOMOGENEOUS the same throughout
also called a solution
Ex: salt water, brass
HETEROGENEOUS
NOT the same throughout
different properties in different parts of the same mixture
Ex: sand & water, granite

10. REVIEW OF 3-4 (Mixtures & Pure Substances)
Is milk a mixture or pure substance?
What do you think about chocolate milk?
Homogeneous mixture. It’s a mixture of water, sugar, fats and proteins that is usually the same composition throughout.
Heterogeneous mixture. It’s a mixture of water, sugar, fats, proteins & cocoa that usually has a lot more chocolate on the bottom of the glass than at the top… YUMMY 

11. REVIEW OF 3-3 (Elements & Compounds)
Passing an electric current through a certain substance produces oxygen and sulfur. This substance cannot be a(n)
compound.
mixture.
element.
solution

12. REVIEW OF 3-3 (Elements & Compounds)
Which of the following is a mixture?
sodium chloride
carbon dioxide
sucrose
air

13. REVIEW OF 3-2 (Chemical vs. Physical Change)
TRUE or FALSE:
Heating water, causing it to boil is a chemical change.
FALSE…Liquid water becomes gaseous water when it boils, but it’s still H2O!
(this is a physical change)
Chemical changes occur when different substances are produced.

14. REVIEW OF 3-2 (Chemical vs. Physical Change)
A substance’s ability to change into different substances is called a:
physical property
physical change
chemical property
chemical change

15. REVIEW OF 3-2 (Chemical vs. Physical Change)
Classify the following as chemical or physical changes:
gold melting
natural gas burning
crushing an
aluminum can
leaves turning
colors in the fall
PHYSICAL
CHEMICAL
PHYSICAL
CHEMICAL

16. REVIEW OF 3-1 (States of Matter)
Which of the following states of matter takes the shape of its container and has a fixed or definite volume?
solid
liquid
gas
plasma

17. REVIEW OF 3-1 (states of matter)
Rank the three most commonly cited states of matter from highest to lowest energy:
solid, liquid, gas
liquid, gas, solid
solid, gas, liquid
gas, liquid, solid