Upload
gordon-phelps
View
217
Download
2
Tags:
Embed Size (px)
Citation preview
• Elements• Simplest form of matter• Cannot be broken down into smaller stable
state of matter• Compounds
• Combination of elements in whole number ratios
• Can be broken down into smaller components
Elements and Compounds
Physical Properties• Can be observed/measured
without changing the composition.
• Examples are density, solubility and state of matter
• Intensive do not depend on amount (density and boiling point)• Extensive do depend on amount (mass, volume)
• Can only be observed with a change in the composition
• Examples are rusting and flammability
Chemical Properties
Properties of Matter
Every substance has unique physical and chemical properties
• Physical changes• Change in a substance that results in different
appearance but not composition• Examples are bending and change in state of matter• States of matter
• All particles in constant motion
• Solids have a definite shape and volume
• Liquids have a definite volume but not a definite shape
• Gases have neither a definite shape nor a definite volume
• Chemical changes (chemical reactions)• Change in a substance that results in one or more new
substances• Indicators are smoke, heat, light, odor• Initial materials are reactants; final materials are products
Changes in Matter
These laws help to explain the behavior of atoms during chemical reactions (changes)
Laws of Chemistry
•True• False
• False
•True•True
All matter is composed of extremely small particles called atomsAll atoms of a given element are identical, having the same size, mass and chemical properties. Atoms of specific elements are different from any other elementAtoms cannot be created, divided, or destroyedDifferent atoms combine in small whole number ratios to form compoundsAtoms are separated, combined, and rearranged in reactions
Dalton’s Atomic Model
• Early experiments• Thompson
• Cathode ray tube• Discovered electrons (1st subatomic particle)• Plum pudding model/chocolate chip cookie dough ice
cream• Rutherford
• Gold foil experiment• Discovered nucleus• Later discovered protons
Atomic Structure Discovery
Basic Atomic Structure
Central dense region of an atom with two subatomic particles
Empty space surrounding the nucleus of an atom
Negatively charged subatomic particle
Nucleus
Positively charge subatomic particleProtons
Electrons
Neutrons
Electron cloud
Subatomic particle without a charge
Atomic Differences
Atomic numberIdentifies the atom as a specific element
Indicates the number of protonsIn a neutral atom, protons = electrons
Mass numberIndicates the number of protons and
neutronsAtoms with same number of protons but
different number of neutrons are isotopes
Atomic mass numberWeighted average of mass of all isotopes
Radioactivity• Nuclear reaction involving a change to the atom• Atom becomes more stable/less energy• Radiation is emitted
• Alpha ( particle– Helium nucleus• Beta ( particle – neutron splits• Gamma ( ray – energy released usually with
an alpha or beta particle
BohrProposed energy states are involved with atoms
Ground state is lowest energy for an atomExcited state is energy is gained by the atom
Also proposed atomic orbitalsElectrons travel around the nucleusAssigned quantum numbers to each energy level
One is closest to the nucleus, then two, etcElectrons can move from energy level to energy level
de Broglie – Wave Particle DualityHeisenberg Uncertainty Principle
Impossible to know velocity and location of an electron at the same time
Atomic Orbitals
Area around nucleus indicating location of electronsPrincipal quantum numbers/Energy levels
Indicate size and energy of atomic orbitalsNumbered from 1 to 7
Energy sublevels are found in the energy levelsAre s, p, d, or f as determined by their shape (p. 133)Each sublevel has orbitals holding two electrons each
s has one orbitalp has three orbitalsd has five orbitalsf has seven orbitals
Energy level 1 has 1 sublevel, 2 has 2 sublevels, 3 has three sublevels, 4 has 4 sublevels
Electron ConfigurationsArrangement of electrons in an atomThree rules define locationAufbau principle
Electrons occupy lowest energy position (p.138)
Each orbital in a sublevel has the same energyOrbitals of different energy levels can overlap
Pauli exclusion principleElectrons spin and in an orbital they are opposite
Hund’s ruleNegative charge plays a role in location One electron per orbital before a second one fills
Exceptions are possible (d block)
Electron Configurations (cont)NotationsElectron configuration notation
Uses energy level, sublevel and number of electrons1s2 2s2 2p3 is nitrogen
Orbital diagramBox represents each orbital with energy level and sublevel written below itElectrons are represented with opposite
arrows
Valence ElectronsElectrons in the outermost energy levelDetermine the properties of an atomDetermine position on periodic tableNoble gases have full outer energy levels (most stable elements)
Electron Dot StructuresOne dot for each valence electronFill on sublevel at a time
• This text is a placeholder.• Here is the second level.• You may change this text
• Here is the third level
• Formatting is controlled by the slide masterand the layout pages.
• There is a third level
• And even a fourth level
• Add a subtitle here•Main Content Page Layout
An accent, click to edit the text inside.
An accent, click to edit the text inside.
• A placeholder for text for the first picture
• More information can be added here by changing this text.
• A placeholder for the second picture
• More information can be added here by changing this text.
•Two Picture Page LayoutA second line of text here
• A description of the first picture. You may change this text.
• A second place holder is available here. Add as much text as you would like.
• A description of the second picture. You may change this text.
• A second place holder is available here. Add as much text as you would like.
• A description of the third picture. You may change this text.
• A second place holder is available here. Add as much text as you would like.
•Three Picture Page LayoutA second line of text may go here.
Here is the description of the table. You may change or delete this text as you wish.
This chart is compatible with PowerPoint 97 to 2007.
Here is a placeholder for more text and description of the chart. Changing this text will not interfere with the formatting of this template.
•Table Page LayoutA second line of text can go here.
Geographic Region
Q1 Q2 Q3 Q4
United States 1254 1254 1254
1254
Europe and Asia
324 324 324 324
Australia 32 32 32 32
South America 2 2 2 2
Canada 1 1 1 1
Mexico 1 1 1 1
TOTALS 1614 1614 1614
1614
Here is the description of the chart. You may change or delete this text as you wish.
This chart is compatible with PowerPoint 97 to 2007.
Here is a placeholder for more text and description of the chart. Changing this text will not interfere with the formatting of this template.
•Line Graph Page LayoutPowerPoint 97 through 2007 Compatible
Here is the description of the chart. You may change or delete this text as you wish.
This chart utilizes features only available with 2007.
Here is a placeholder for more text and description of the chart. Changing this text will not interfere with the formatting of this template.
•Bar Graph Page Layout PowerPoint 2007 Enhanced Version
Here is the description of the chart. You may change or delete this text as you wish.
This chart utilizes features only available with 2007.
Here is a placeholder for more text and description of the chart. Changing this text will not interfere with the formatting of this template.
•Pie Graph Page Layout PowerPoint 2007 Enhanced Version
This chart utilizes Smart Art which is feature in PowerPoint 2007. If you wish to make charts like this and don’t have PPT 2007, we have provided the graphical elements to help you build this yourself.
Here is the description of the chart. You may change or delete this text as you wish.
Here is a placeholder for more text and description of the chart. Changing this text will not interfere with the formatting of this template.
•Smart Art Page Layout PowerPoint 2007 Enhanced Version
•Picture Page LayoutPicture Caption Here
Animation PageMake an Impact in your presentations by adding some themed PowerPoint animations.