1. Chemistry Draw a Bohr Model of a carbon atom.
(Turn to page 269 of your textbook.)

2. List common elements & chemical symbols. Example: Carbon C
Chemistry
List common elements & chemical symbols.
Example: Carbon C

3. List common elements & chemical symbols.
Chemistry
List common elements & chemical symbols.
Example: Carbon C
Hydrogen H
Oxygen O
Carbon C
Iron Fe
Sodium Na
Magnesium Mg

4. Identify Chemicals
Chemical: substance used in or formed by a chemical process.
Synthetic Chemical: a chemical that is not formed in nature and is made by people.
Matter: anything that has mass and volume.
Element: a substance that cannot be broken down into simpler substances by ordinary chemical means.
Synthetic element: elements that are made by scientists in a laboratory and do not exist in nature.
Mixture: a type of matter that forms when two or more substances are combined but do not join together chemically.
Compound: a type of matter that forms when two or more elements combine chemically.

5. Chemicals

6. Compounds
Molecule: the smallest unit of a compound that has all the properties of the compound.
Chemical Formula: uses chemical symbols and subscripts to identify the number of atoms of each element in a molecule of a compound. Example: H2O is water.
Atom: the smallest unit of an element that has all the properties of the element.
Proton: a particle with a positive charge.

7. Compounds Neutron: neutral particle, does not have a charge.
Electron: has a negative charge.
Nucleus: central core made of protons and neutrons.
Valence Electrons: electrons in the outermost energy level of an atom.
Ionic bonds: bonds formed by the transfer of electrons.
Ion: an atom that has gained or lost one of more electrons.
Covalent bond: formed when two atoms share electrons.

8. What is a compound?
A compound is a pure substance that is created by 2 or more elements chemically reacting and joining together
Ex: NaCl, H2O, CO2, NH3, NaHCO3, and C6H12O6
Compounds form to allow elements to become more stable
Na is flammable when it comes in contact with H2O, and Cl2 is a toxic gas
NaCl is a very stable compound that is neither flammable nor toxic (in normal quantities)

9. What is a mixture?
A mixture is the physical combination of 2 or more substances
It is important to understand that a mixture is not chemically combined
Mixtures can be separated by physical means such as filtration, distillation, and chromatography
Remember no chemical change is occurring

10. What is a mixture? Homogeneous mixtures are commonly called solutions.
Solution = Solute + Solvent
Solute: “stuff” being dissolved
Solvent: “stuff” doing the dissolving
The solvent is present in greater quantity
The solute is present in the lesser quantity
Ex: Salt water: Salt=solute, Water=solvent

11. How is it all related?
Protons
Electrons
Neutrons
Atoms
Matter

12. What are properties?
Property: a characteristic of a substance that can be observed
Physical property: a property that can be observed without changing the identity of the substance.
Luster
malleability: the ability to be hammered into a thin sheet
ductility: the ability to be stretched into a wire
Magnetism
Electrical/thermal conductivity
Solubility

13. Special Physical properties
Melting point: the temperature at which a substance changes from a solid to a liquid at a given pressure
water = 0oC
Boiling point: the temperature at which a substance changes from a liquid to a gas at a given pressure
water = 100oC
Density is the amount of mass per unit of volume.
Density, melting point, and boiling point can be used to identify a substance.
The density of water is 1.0g/mL

14. Chemical Properties
Chemical property: a property that can only be observed by changing the identity of the substance
Examples:
flammability
ability to rust
reactivity with vinegar

15. Changes
Physical change: a change that occurs that does not change the identity of the substance
Melting ice(change in state or phase)
Freezing Kool-aid
Tearing paper
Boiling water (same as melting ice)
Chemical change: a change that occurs causing the identity of the substance to change
Burning
Digesting food
Reacting with other substances
A chemical change is called a chemical reaction

16. Chemical Changes Indicators of a chemical change:
Evolution of light
Evolution of heat
Evolution of a gas
Color change
Formation of a precipitate (solid that forms from a chemical reaction)
Chemical reaction (also known as a chemical change) is a change in a substance or substances that results in a totally new substance
Ex: 2H2(g) + O2(g)  2H2O(g)
Notice that the reactants (the substances you start with) combine to form a new substance (the product)

17. Chemical Reaction
It is important to understand that when matter undergoes a chemical reaction (ie, a chemical change) it does not disappear or appear
The atoms are rearranged and form new bonds, but no matter is lost nor gained
This is called the Law of Conservation of Matter
Therefore, if you start with 10 atoms of oxygen, you must end with 10 atoms.

18. The Atomic Theory Key Ideas Explanation
All matter is composed of atoms.
Atoms of a given element are identical.
Atoms of different elements combine in simple whole-number ratios to form chemical compounds.
Explanation
Atoms are the building blocks of matter.
All atoms of the same element have the same number of protons and electrons.
The ways atoms combine to form compounds is determined by the valence electrons of an element.

19. What are atoms? Atoms are the building blocks of matter
Atoms are too small in size to study easily
Size of Earth : soda can = soda can : atom
The nucleus contains protons (positive charged) and neutrons (no charge). The nucleus is surrounded by the electron (negative charge) cloud.

20. What are atoms?
Protons and neutrons live compacted in the tiny positively charged nucleus accounting for most of the mass of the atom
The negatively charged electrons are small and have a relatively small mass but occupy a large volume of space outside the nucleus

21. Balance In an atom: The protons = the electrons
If 20 protons are present in an atom then 20 electrons are there to balance the overall charge of the atom—atoms are neutral
The neutrons have no charge; therefore they do not have to equal the number of protons or electrons

22. Balance
Atomic number: this number indicates the number of protons in an atom
Ex: Hydrogen’s atomic number is 1
So hydrogen has 1 proton
Ex: Carbon’s atomic number is 6
So carbon has 6 protons
**The number of protons identifies the atom.
Ex. 2 protons = He, 29 protons = Cu

23. Atoms Mass number: the number of protons and neutrons in the nucleus
Ex: hydrogen can have a mass of 3.
Since it has 1 proton it must have 2 neutrons
# of neutrons = mass # - atomic #
The electrons are equal to the number of protons
So e- = p = atomic #
Ex: He has a mass # of 4 and an atomic # of 2
p+ = 2
no = 2
e- = 2

24. Bohr Model Bohr Model of the atom: All of the protons and the neutrons
The 3rd ring can hold up to 18 e-
The 1st ring can hold up to 2 e-
The 4th ring and any after can hold up to 32 e-
The 2nd ring can hold up to 8 e-

25. Periodic Table
Atomic mass: is equal to the number of protons and neutrons in the nucleus of one atom of the element.
Periodic table: a chart that organizes information about all of the known elements according to their properties.
Atomic number: the number of protons contained in each nucleus of its atom.

26. Periodic Table Period: horizontal row in the periodic table.
Group: Vertical column on the periodic table or chemical family.
Reactivity: how likely an element is to form bonds with other elements.
Metalloids: elements that have some properties of both metals and nonmetals.
Inert: unable to react chemically.

27. Block of Periodic Table Label the different parts.2 He
4.0026
Helium

28. Labeled Element 2 He 4.0026 Helium Elemental Symbol
Atomic Number = # of protons
Atomic Mass = # of protons plus neutrons

29. Periodic Table http://www.accessscience.com/periodicTable.aspx Only
nonmetal on the metal side
Nonmetals are on the right of the stair-step
Metals are to the left of the stair- step
Semi-metals,
“metalloids,”
touch the stair-step

30. Properties of Metals and Nonmetals
Properties of Nonmetals
Most are gases, except bromine, which is a liquid.
Are brittle in the solid phase
Have a tendency to be dull, not shiny and bright
Are poor conductors of heat and electricity
Tend to gain electrons in chemical reactions
Properties of Metals
Solid at room temperature, except mercury, which is a liquid
Malleable and ductile
Have luster- are shiny
High conductivity- are good conductors of electricity and heat
Tend to lose electrons in chemical reactions

31. Groups
Group 1- Alkali metals, easily combine with nonmetals, have one valence electron.
Group 2- Alkaline Earth metals, reactivity but not as reactive as group one, two valence electrons, reactivity increases with increasing atomic number.
Group Transition Metals, generally hard solids with high melting points.
Group First element in column is the name of that group, subtract 10 from group number to get number of valence electrons.
Group 17- Halogens, most reactive nonmetals, reactivity increases as atomic number decreases.
Group 18- Noble gases, least reactive, will form compounds under extreme conditions (except Helium).

32. Types of Bonds Covalent Bonds
Atoms seek to have 8 valence electrons in outer level, so they share electrons.
Forms a molecule of nonmetals only.
A molecule can be made up of atoms of the same element or atoms of different elements. For example Cl2 or H2O.
Ionic Bonds
Atom that loses electrons becomes a positive ion.
Atom that gains electrons becomes a negative ion.
Bond between metal and nonmetals.
Example: Sodium Chloride (NaCl)

33. Periodic Table Challenge
How many words can you make using the chemical symbols in the Periodic Table?
You may use the symbols more than once in a word, but you cannot mix up the letters. The symbols must be used as they appear in the Periodic Table. You may also use words with only one or two letters as well as the names of people, places, and other elements.
You must provide the symbols (in correct format) as well as the word.
Examples: He + At = Heat
N + O + B + O + Dy = Nobody