Molar Mass

molar mass - the mass (g) of 1 mole of a substance
-the molar mass is the atomic mass
-molar mass is measured in g/mol

Molar Mass of Compounds
-to determine the molar mass of a compound, you add the mass of all the atoms together
EX.
C12H22O11 --> 12.0(12)+1.0(22)+16(11) = 342.30g/mol
KCl --> 19+17 = 36g/mol
NaBr4 --> 23.0 + 79.9(4) = 342.6
(NH4)2S --> (( 14+1 (4) )) x2 + 32.1 = 54.1g/mol

Janine Roldan

Chapter 2 Test

A review of chapter 2:

Atomic theories

JJ Thomson - raisin bun theory
                    - he beleived there was a solid, postive sphere with negative
                       particles embedded



Bohr and Lewis Diagrams



Quantum Mechanics


S orbital - each orbital holds 2 electrons
P orbital - 3 suborbitals: contain 2 electrons each
D orbital - 5 suborbitals: contain 2 electrons each
F orbital - 7 suborbitals: contain 2 electrons each

Naming Compunds



IUPAC= using roman numerals in pararanthesis
Classical System= use latin names of the element
ex. Aunn: gold
      Ferr: iron
- when using the classical system the larger charge you use ic and the smaller charge ous

Nicole H

Hydrate Lab (November 4)

The purpose of this experiment was to determine the empirical formula of hydrate. In this lab we determined the anhydrous(w/out water) mass of the hydrate. We also compared this with the actual mass of water that should have been present.


Janine Roldan

Molecular Compounds

Molecular Compounds

• molecules are diatomic 
• 2 of the same elements: H2, N2, O2, F2, Cl2, Br2, I2
• 2 molecules are polyatomic: S8, P4

Naming Molecular Compounds

• use the name of the first element
• second element ends in -ide
• 1st atom usually doesn't have a prefix EX. CO2 -> carbon dioxide
• hydrogen doesnt have a prefix EX. H2S -> hydrogen sulfide

More examples:

HBr -> hydrogen bromide

KI -> potassium iodide

H20 -> dihydrogen oxide

Naming Acids and Bases

• hydrogen compounds are acids

EX. 

HCl -> hydrochloric acid

H2SO4 -> sulfuric acid

Naming Bases

• cation and OH

EX.

Na(OH) -> sodium hydroxide

Ba(OH)2 -> barium hydroxide

Sofia Nguyen

Naming Compounds

Chemical Nomenclature

Todays most common system is IUPAC for most chemical reactions like:
- ions
- binary ionic
- polyatomic ions
- hydrates
-molecular compounds
- acids/ bases

Chemical Formulas
- be aware of the difference between and ion and a compound.
ion= charge
compound= no charge



Note: -the top charge on a multivalent is the most commonly used
           -IUPAC use roman numerals in parenthesis
           - classical systems use latin names of the elements

suffixes ic is the larger charge and ous is for the smaller charge
ex. Fe0 - ferrous oxide

Classical names are a bit different for some elements like:
Ferr : iron
Cupp: copper
Stann: tin
Plumb: lead

Hydrates
some compounds can form lattices that bond to water molecules by hydrates

-watch this video to learn how to make/ name hydrates
http://www.youtube.com/watch?v=HM2C5FEvR0g

Nicole Haughian

How to Draw Electron Dot Diagrams

Electron Structure: Electron Dot Diagrams

Drawing Electron Dot Diagrams


follow this link --> http://www.youtube.com/watch?v=y6QZRBIO0-o (:


Lewis Diagrams for Compounds and Ions

·                     in covalent compunds electrons are shared

·                     one atom gives up an electron to the other, forming positive and negative ions

1.                   First determine the number of valence electrons for each atom in the molecule

2.                  Then, place atoms so that valence electrons are shared to fill each orbital

EX.

carbon tetrafluoride

Double and Triple Bonds

EX.

oxygen: it's outer shell contains 6 electrons so it needs another 2 electrons in this case shared to get a stable configuration

Ionic Compounds

·                     the formation of an ionic bond is the result of the transfer of one or more electrons from a metal to a non-metal

·                      draw [brackets] around the metal and non-metal

·                     for metals: Energy + Metal Atom ---> Metal (+) ion + e-

·                     for non-metals: Non-metal Atom + e- --- Non-metal (-) ion + energy

EX.

JANINE ROLDAN

Trends on the Periodic Table.

 There are some things on the periodic table that you wouldn't know about just by looking at it, but by actually studying and researching about it.

Did you know that elements close to each other on the periodic table display similar characteristics? 

TRENDS

There are 7 important periodic trends that you'd have to know;

1. Reactivity

2. Ion Charge

3. Melting Point

4. Atomic Radius

5. Ionization Energy

6. Electronegativity

7. *Density 

You actually don't need to know much about density.

REACTIVITY

• Metals and non-metals show different trends
• The Most reactive metal is Francium; the most reactive non-metal is fluorine.

ION CHARGE

• Elements that that contain ion charges depend on their group (column)

MELTING POINT

• Elements in the center of the table have the highest melting point
• Noble gases have the lowest melting points
• starting from the left and moving right, melting points increase until the middle of the table

ATOMIC RADIUS

• Radius decreases up the right 
• Helium has the smallest atomic radius 
• francium has the largest atomic radius

IONIZATION ENERGY

• Ionization energy is the energy needed to completely remove an electron from an atom
• it increases going up and to the right of the periodic table
• all noble gases have high ionization energy
• Helium has the highest ionization energy and Francium has the lowest ionization energy

ELECTRONEGATIVETY

• Electronegativity refers to how much atoms want to gain electrons
• some trend such as ionization energy

IF YOU WANT TO LEARN MORE PLEASE REFER TO THE FOLLOWING LINKS! :)

http://chemistry.about.com/od/periodictableelements/a/periodictrends.htm

http://dl.clackamas.cc.or.us/ch104-06/periodic.htm

A SONG THAT COULD HELP YOU REMEMBER THEM

http://www.youtube.com/watch?v=dHcD_But7dU

http://www.youtube.com/watch?v=dHcD_But7dU

SOFIA NGUYEN