1. Final Exam Review: Properties & Phases of Matter

2. Matter Matter is anything that has mass and takes up space.
Atoms are the building blocks of matter.

3. ELEMENTS and COMPOUNDS
An element is the simplest type of a pure substance. It cannot be broken down into any other substances by chemical or physical means.
Elements combine to form compounds.
A compound is a substance formed from the chemical union of two or more elements.

4. Solutions A solution is a well-mixed mixture.
Solutions are homogeneous and contain a solute and a solvent.
Example- Sugar dissolved in water. Sugar is the solute, water is the solvent.

5. MIXTURES
A mixture is made from two or more substances that are together in the same place but not chemically combined.
A heterogeneous mixture appears to be different throughout.
A homogeneous mixture appears to be the same throughout.

6. Compounds Mixtures chemically combined NOT chemically combined
do NOT keep their original properties
keep their original properties
combined in a specific ratio
NOT combined in a specific ratio
cannot be broken down by simple chemical methods
can be broken down by simple chemical methods

7. Phases of Matter Matter can take 4 different phases or states: Solid
Liquid
Gas
Plasma

8. Phase Shape Volume Solid Liquid Gas Plasma Definite Definite
Indefinite
Definite
Indefinite
Indefinite
Indefinite
Indefinite

9. S L Melting
L S Freezing
L G Evaporating
GL Condensing

10. ATOMIC STRUCTURE Atoms are made up of 3 subatomic particles
Protons are positively charged subatomic particles found in the nucleus. They each have a mass of 1 amu. The number of protons is the atomic number of the element and so tells the identity of the element
Neutrons have no charge and are also found in the
Nucleus of the atom. Atoms of an element may contain
Various numbers of neutron which are called isotopes of the element.
Neutrons have a mass of 1 amu each.
Electrons are negatively charged subatomic particles found in an electron cloud around the nucleus. They are soooooo small that they are not considered to add mass to the atom.

11. Isotopes
Remember that all atoms of a particular element have the same number of protons, but that these atoms may have different numbers of neutrons in the nucleus
These all represent the nucleus of a carbon atom (atomic # 6)
6 p+
6 p+
6 p+
6 n
8 n
7 n
Each atom of carbon can have different numbers of neutrons. These are 3
Isotopes of the carbon atom.

12. Information from the periodic table block
The atomic number tells the number of protons in the nucleus of the atom. The table is arranged in order of increasing atomic number.
The average atomic mass when rounded to the nearest whole number tells the total amu in the nucleus of the atom. If you subtract the number of protons from this number, you will determine the number of neutrons in the nucleus.
The electron configuration shows how many electrons there are in each energy level. It allows you to see the number of valence electrons in the outer energy level of the atom.
You will also find the name, and the symbol for each element in this block.

13. Atoms and the periodic table
The atomic number is the number of proton in an element
Electron configuration indicates the number of electrons in each energy level 6 O
oxygen
The average atomic mass is not a whole number because it is an average of the masses of all the isotopes of an element.

14. PERIODIC LAW Metals are to the LEFT of the Zig-Zag
Non-Metals are to the RIGHT of the Zig-Zag
METALLOIDS are found along the line

15. There are 7 rows or periods on the table
There are 7 rows or periods on the table. Elements in a periods all have the same number of energy levels. If the element is in period 3, it has 3 energy levels

16. PROPERTIES OF Metals and nonmetals
Metals are electron donors
Metals have 3 or less valence electrons
Metals are good conductors of heat and electricity and are malleable and ductile
Metals are found on the left of the step on the periodic table
Nonmetals are electron recipients
Metals have 5 or more valence electrons
nonmetals are poor conductors of heat and electricity and are britlle
Nonmetals are found on the right of the step on the periodic table

17. Families of elements are found in the columns on the periodic table
Families of elements are found in the columns on the periodic table. Elements in a column or family or group have similar chemical properties because they have the same number of valence electrons

18. CHEMICAL REACTIONS Four types of chemical reactions are
synthesis reaction
Two simple substance combine to form a more complex substance A + B yields AB
Decomposition reaction
a complex substance breaks down into two or more simple substances AB yields A + B
Single replacement reaction
an uncombined element replaces an element in a compound
A + BC yields AC + B
Double replacement reaction
two elements replace each other in two compounds
AB + CD yields CB AD

19. Chemical reaction continued
Evidence that a chemical reaction has occurred is the formation of new substances
Each chemical equation must be balanced so that all the atoms of each element are the same on both sides of the arrow. This is called the Law of Conservation of mass and means that matter cannot be created or destroyed during a chemical reaction
A chemical reaction that absorbs energy and yields products that are colder than the reactants is ENDOthermic
A chemical reaction that releases energy and becomes warmer than the reactants is called EXOthermic
To increase the rate of a chemical reaction you can
Increase the heat energy
Increase the surface area of the substance
Increase the concentration of the reactants

20. ACIDS AND BASES
pH is measured by using a scale that goes from 0 to 14. pH is an abbreviation for the presence of H ions in a solution
7 represents a neutral pH
The further away from neutral, the stronger the acid or the base
So a pH of 12.3 would indicate a very strong base and a pH of 2.1 would
indicate a very strong acid.

21. CONCLUSION
WE HAVE CERTAINLY LEARNED A GREAT DEAL ABOUT LIVING THINGS AND CHEMISTRY! I hope this year has been as rewarding and exciting for you as it has been for me. You are a talented and caring group of young people and I will miss you very much.
Please be sure to visit when you are in the 8th grade next year. Have a wonderful and restful summer. Always be amazed at the world around you.