• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
Chapter 2 Notes
 

Chapter 2 Notes

on

  • 2,599 views

 

Statistics

Views

Total Views
2,599
Views on SlideShare
1,912
Embed Views
687

Actions

Likes
0
Downloads
10
Comments
0

4 Embeds 687

http://blendedschools.blackboard.com 672
http://www.blendedschools.blackboard.net 13
http://www.blendedschools.blackboard.com 1
http://blendedschools.blackboard.net 1

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    Chapter 2 Notes Chapter 2 Notes Presentation Transcript

    • POWER UP 2-1
      • 1. Explain the difference between an electron and a proton.
      • Name the particle that has a neutral charge in an atom.
      • Mass
      • Atoms
      • Electrons and Nucleus
      • Nucleus
    • Chapter 2 Matter & Its Changes PART 1
    • 2.1 Atoms
      • Matter: anything that has mass and takes up space
        • Taking up space = volume
      • Matter comes in 4 states:
        • Solids: matter with definite shape
        • Liquids: matter that has the ability to flow
        • Gas: vaporized form of matter
        • Plasma: High Energy state of matter
      • All matter is made up of atoms
      Pgs. 32 - 37
    • The Atom
      • Atom: smallest particle of any element that has the properties of the element
        • Cannot be seen
        • Only indirectly observed
        • Make up everything that has mass and volume
    • Parts of an Atom
      • Atoms are made up of 3 particles
        • Electron: particle that moves around the nucleus forming a cloud of negative charge (-)
        • Proton: particle inside the nucleus with a positive charge (+)
        • Neutron: particle inside the nucleus with no charge (neutral)
      • Electrons have almost no mass
      • Protons & neutrons have the same mass
        •  1800 times heavier than an electron
    •  
    • Electron Cloud
        • Electrons orbit a nucleus in areas known as Electron Clouds
          • Electrons are found in energy levels (shells)
          • The farther from the nucleus a shell is, the higher the energy level
            • The shell closest to the nucleus can only hold 2 electrons
            • The second shell holds up to 8 electrons
            • The third shell holds up to 18 electrons
            • The fourth shell holds up to 32 electrons
            • Shells farther out hold up to 64 electrons
              • Electrons try to arrange in pairs
      Helium Neon Krypton
    • Ex: Magnesium (Mg)  Atomic Number = 12 12 protons, 12 electrons
      • Shell #1 = 2 electrons
      • Shell #2 = 8 electrons
      • Shell #3 = 2 electrons
      • Total = 12 electrons
      • We can draw all atoms
      • in a similar style
    • Elements
      • Elements: substance made up of only 1 kind of atom
        • Cannot be broken down by physical or chemical means
        • Use Symbols to represent elements
          • H  Hydrogen Fe  Iron
          • He  Helium Au  Gold
          • C  Carbon Na  Sodium
        • Some are 1 letter, others are 2 or 3 letters
          • First letter is ALWAYS capitalized
          • 2 nd and 3 rd are lower case
          • Prevents confusion:
            • Co  Cobalt (element)
            • CO  Carbon Monoxide (Compound of Carbon (C) & Oxygen (O)
    • Elements’ Names and Symbols:
      • Some symbols come from the common name
        • O  Oxygen N  Nitrogen Ne  Neon
      • Some symbols come from the Latin name
        • Fe  Iron (from Ferris)
        • Na  Sodium (from Natrium)
        • Pb  Lead (from Plumbum) “Plumber  Lead smith”
      • Newest elements are produced in Labs
        • Names given by creator
        • Symbols usually 3 letters
    • All atoms of the same element must have the same number of protons
      • We use the number of protons to classify elements
        • Number of protons is called: the atomic number
          • Ex: All Hydrogen atoms have 1 proton
          • All Carbon atoms have 6 protons
      • Atoms tend to be electrically neutral
        • Number of electrons = number of protons ( -’s = +’s)
          • Number of neutrons can be different
        • Protons and Neutrons are made up of quarks
          • 2 quarks = 1 proton or 1 neutron
          • Quarks have silly names: up/down, happy/sad, etc.
    • Elements are arranged on the Periodic Table of Elements
    • The Periodic Table
      • Dimitri Mendeleev:
      • Russian Chemist (1869)
      • Classified all known elements
        • Arranged elements by mass
        • Noticed repeating patterns
        • Began a new row every time pattern began
      • Called arrangement: Periodic Table of Elements
      • Periodic means “to repeat”
        • Periodic Table: elements arranged in rows according to atomic number and in columns by properties
    • Mendeleev’s Table
    • Element info.
      • Atomic Number : # of Protons = # of electrons
      • Mass number : Protons + Neutrons
      • Atomic Mass : Average mass of all isotopes for an element
      • NOT TO BE CONFUSED with Mass Number
      • (Protons + Neutrons)
      5 B 10.81 Atomic Number Atomic Symbol Atomic Mass
    • Dimitri had some blanks in his table. He predicted these were undiscovered elements
      • From the pattern on his table, he was able to predict properties about the missing elements
      • The Periodic Table gives information about each element
      1 H Hydrogen 1.00794 Atomic Number Atomic Symbol Element Name Atomic Mass
    • Atomic Mass Number
      • Mass of an atom depends on the number of protons (Atomic Number) and neutrons in its nucleus
      • Protons + Neutrons = Mass Number
        • Ex: Carbon (C) P = 6 N = 6 Mass = 12
        • Sodium (Na) P = 11 N = 12 Mass = 23
        • Iron (Fe) P = 26 N = 30 Mass = 56
      • By using mass number and Atomic Number, the number of neutrons can be found
        • Potassium (K) Mass = 39 Atomic Number = 19
        • Mass Number – Atomic Number = Neutrons
        • 39 – 19 = 20 Potassium has 20 neutrons
    • Isotopes
      • All atoms of the same element must have the same number of protons (Atomic Number)
      • But, their number of neutrons can be different
      • Isotopes: atoms of the same element with different number of neutrons
        • Ex: Hydrogen has 1 proton, but can have 0, 1, or 2 neutrons = 3 isotopes (each having different masses)
      Hydrogen Deuterium Tritium
    • Carbon Isotopes:
      • Carbon has 6 protons;
        • Some have 6 neutrons,
        • Others have 8 neutrons
          • Carbon – 12 (6 + 6) is normal
          • Carbon – 14 (6 + 8) is an isotope
            • Carbon – 14 is radioactive
            • Used in carbon dating
                                                                                
    •  
    • Drawing Atomic Models
      • Name Atom
      • Write number of protons
      • Write number of neutrons
      • Draw shells and electron pairs
        • Remember how many electrons
        • each shell can hold
        • (2, 8, 18, 32, etc.)
      Carbon P = 6 N = 6
    •  
    • 2.2 Combining Atoms
      • Atoms join by chemical bonds to form unique substances
      • How they join is important
        • Hydrogen (H)  elemental gas ( Explosive )
        • Oxygen (O)  elemental gas ( Needed for combustion )
        • H 2 0  water ( puts out fires )
        • H 2 0 2  Hydrogen Peroxide ( Antiseptic & bleach )
      • How atoms combine
        • Compounds form during chemical changes only
        • Atoms rearrange positions
        • Changes depend on Chemical Activity
        • Based on electrons in outer shell
        • Atoms will always try to form stable bonds
      Pgs. 38 - 43
        • Covalent bonding produces molecules
        • Ionic bonding produces compounds
        • Y E S ,
        • there is a difference !!!!
      Special Note
    • Molecules
      • Covalent bond: formed by atoms sharing electrons producing a molecule
      • Molecule: Neutral particle formed by sharing of electrons
      • This differs from ionic bonding in that it forms a new particle; ionic bonding is just an ordered grouping of ions held together by charges
      • Many elements exist in nature as molecules
        • O 2 , N 2 , H 2 , any halogen (diatomic molecules)
        • H 2 O, HCl, and H 2 O 2
    • Electron Sharing
      • Atoms can share electrons
        • Ex: Chlorine gas (Cl 2 )
        • 2 Chlorines have 7 electrons in their outer shell
        • Both want 8
        • Electrons fit together like puzzle pieces, forming covalent bonds
    • Compounds
      • Compound: unique substance formed when 2 or more elements combine chemically
        • Impossible to be separated by physical means
        • Forms new substance
        • Compound properties differ from the elements making it up
          • Ex: H 2 0, NaCl
      • Elements always combine in specific ratios
        • CO  Carbon Monoxide 1:1
        • CO 2  Carbon Dioxide 1:2
    • Electron Loss and Gain
      • Compounds are formed by losing or gaining electrons from their outer shells
      • Ex: Sodium Chloride (NaCl)
        • Sodium (Na) has 1 electron in its outside shell
          • Atomic Number = 11 (2, 8, 1) {Wants to lose 1}
        • Chlorine (Cl) has 7 electrons in its valence level
          • Atomic number = 17 (2, 8, 7) {Wants to gain 1}
        • If Na loses 1 electron it will become stable (2, 8)
        • If Cl gains 1 electron it will become stable (2, 8, 8)
      • Na’s electrons is transferred to Cl
      • Na now has 11 protons and 10 electrons
        • Giving Na a positive charge (+1)
      • Cl now has 18 electrons and 17 protons
        • Giving Cl a negative charge (-1)
      • Na (+1) and Cl (-1) now have opposite charges
        • They have become ions and opposites attract
    • Rule of 8
      • Atoms always try to form stable shells
        • Either they fill the outside shell or they get 8 electrons
        • By sharing, gaining or losing electrons
      • Full shells or 8 electrons in the outside shell makes atoms happy
    • Table Salt: Sodium Chloride (NaCl)
      • Sodium (Na):
        • Shiny; clay like metal; reacts violently in water
      • Chlorine (Cl):
        • Yellow-green gas, very toxic
      • Sodium Chloride (NaCl): white, crystallized solid
        • Seasoning for foods
        • Preservative & used for dehydration (water removal)
    • Chemical formula: a group of symbols that represent a compound
        • Shows elements along with ratios
        • The small “2” is called a subscript
          • Is a number that shows how many atoms of each element combine to form a compound
          • Absence of a subscript means one
        • CO 2
      • 1 Carbon 2 oxygen
    • We use prefixes when naming compounds
      • Prefix tells the number of atoms per element
        • Carbon Mono xide (CO) Vs. Carbon Di oxide (CO 2 )
        • Triethyl, DiMethyl Tolueen: (Moth Balls)
          • 3 ethyl groups, 2 methyl groups & the compound Tolueen
      • Prefix List:
        • Mono = 1 Tetra = 4 Hepta = 7 Deca = 10
        • Di = 2 Penta = 5 Octa = 8
        • Tri = 3 Hexa = 6 Nona = 9
    • Chemical Formulas
      • Use symbols to represent a compound
      • Shows elements & ratio
        • Ex: C 6 H 12 O 6  Glucose
        • C 6 = 6 Carbons
        • H 12 = 12 Hydrogens
        • O 6 = 6 Oxygens
    • Ions and Ionic Bonding
      • Ion: a charged particle formed when an atom gains or loses electrons
      • Ionic Bonding: the attraction between ions of opposite charges
      • Na (+1) joins with Cl (-1) = NaCl
    • Calcium (Ca) also combines with Chlorine (Cl) to form ionic compounds
      • Calcium Carbonate (Ca Cl 2 ): chalk
      • Calcium loses 2 electrons = +2 charge
      • 2 Chlorines each gain one electron = -1 charges
      • Cl (-1) Ca (+2) Cl (-1)
    • Naming Binary Compounds
      • Binary Compound: two element compound
      • 1.) Name of positive ion (metal) written first
      • 2.) Negative ion name changed to end in “ide”
        • HCl  Hydrogen Chloride
        • KBr  Potassium Bromide
        • NaCl  Sodium Chloride
        • KI  Potassium Iodide
    • Composition of Matter
      • Substances
        • Elements: a piece of matter made up of all the same kind of atoms
          • There are 90 natural elements and over 20 man-made elements
          • Elements are listed on the Periodic Table of Elements
        • Compounds: a substance made up more than one kind of atom, in a specific ratio
          • Water is always 2 Hydrogen & 1 Oxygen (H 2 0)
          • This 2:1 ratio never changes
          • Ammonia: 1 Nitrogen & 3 Hydrogens (NH 3 )
      • Elements & Compounds are Substances , because they have a definite composition
      • MIXTURE: When 2 or more substances are combined
      • Mixtures keeps the properties of each substance
      • Mixtures do not have specific ratios
        • Ice Tea  Mixture (Tea mix, sugar, water)
        • Clothing  Mixture (Cotton, Polyester, Wool, etc.)
    •  
    • 2 Types of Mixtures
      • Heterogeneous mixture: Substances not evenly spread out
        • Ex: Italian Salad Dressing (parts separate into layers)
      • Homogeneous mixture: Substances evenly spread out
        • Also called a Solution  dissolved in liquid
        • Ex: Ice Tea, Sea water, soda
    •  
    • Solutions
      • Homogenous mixtures
      • Particles do not settle out
      • Particles very small (.1 to 1 nanometer)
      • Particles cannot be filtered out
      • Will not scatter light
      • Particles will never separate
      • We call it being dissolved
      • Ex: Soda, Ice tea, Salt water
    • Suspension:
      • Heterogeneous mixture
      • Particles are 1000 nm or bigger (dirt, sand, pebbles, etc.)
      • Particles can be seen with a microscope or unaided eye
      • Particles will settle out over time (By gravity)
        • Ex: Italian Salad Dressing, Muddy water
      • Can scatter light (We see light rays)
    • Colloids
      • Homogenous Mixture
        • Evenly distributed when viewed with a microscope
      • Particle size between solutions & suspensions
        • Between 1 & 1000 nm (Dust, Fine dirt, etc.)
      • Particles will scatter light
      • Colloids have 2 interesting properties
        • Tyndall effect: ability of colloids to scatter light
          • When light passes thru colloids the beam can be seen
          • Dust, Smoke, and fog all have Tyndall effect
          • Ex: Search light, Movie theater
        • Brownian Motion: constant zig zag movement
          • Dust randomly floating through the air
      Tyndall Effect
      • CHAPTER 1 – PART 2
    • 2.3 Matter
      • Property: a characteristics of a substance
      • Physical Property: anything that can be seen or measured without changing the make up of a substance
        • Ex: Boiling Point, Freezing Point, Weight, Color, Odor, Hardness, Density, Magnetic, Etc.
        • Observed by using the senses
          • (See, hear, touch, taste, smell)
        • No 2 substances have exactly the same properties
        • Physical Properties are used to separate mixtures
          • Sand and Marbles  pick out biggest objects
          • Sand and Iron Filings  use a magnet
      Pgs. 44 - 51 Elemental Sulfur Chlorine Gas
    • Physical Change
      • Physical change: process that does not change the chemical composition of a substance
        • Changes in size, shape, etc. but NOT what it is
          • Breaking Glass
          • Cutting wood
          • Changing states
        • Mixtures & solutions can be separated by physical means
          • Ex: Salt water  boil water and salt will be left
          • Wire screen can be used to separate pebbles from sand
    • Chemical Properties
      • Chemical properties: a characteristic that shows how a substance reacts to form other substances
        • Ability to burn is a Chemical Property
        • Corrosion (rusting, oxidizing, etc.) = Chemical Properties
    • Chemical Change
      • Substance changes to a new substance
        • Has totally different properties
        • Wood Burning: changes into ash, gives off heat & Light
        • Steel Rusting: iron joins with oxygen  Iron oxide forms
        • Aluminum forming Aluminum oxide (similar to rusting)
      • Chemical Changes always cause physical changes
    • 3 Specific Chemical Changes
      • Electrolysis: electricity producing chemical changes
        • Water separated into Hydrogen and Oxygen Gas
      • Corrosion: metals chemically changed by combining with other materials (usually oxygen)
        • Silver tarnishing: silver reacts with water and oxygen
      • Combustion: materials burning
        • Organic matter contains Carbon, Hydrogen, Oxygen
        • C 6 H 12 O 6  Energy, CO 2 & H 2 O
          • Heat and Light are produced by the atoms rearranging, and forming new compounds
          • C 6 H 12 O 6  Glucose
          • CO 2  Carbon Dioxide
          • H 2 O  Water
    • States of Matter
      • There are four states of matter
        • Solids, Liquids, gases, plasma
      • Each states is determined by amount of energy
        • Solid: minimal thermal energy
        • Plasma: highly energized, electrically charged particles
          • Plasma naturally occurs on the sun and as lightning
          • We create plasma in fluorescent lights
    • The Normal States of Matter
      • Solids: definite shape, definite volume, definite mass
      • Liquids: definite volume, definite mass
        • No definite shape (takes the shape of a container)
      • Gases: No definite shape, No definite volume
        • Fills entire space it is placed in
        • Only has definite mass
      • Plasma: like gas, has no definite shape or volume
      E N E R G Y I N C R E A S E S D E N S I T Y D E C R E A S E S Bornite
    • Kinetic Theory of matter
      • All matter is made of tiny particles
      • The particles are in constant motion
      • Motion and spacing determine state
      • Higher temperature; more Kinetic Energy causes faster the motion
    • Solids
      • Particles are packed very closely together
        • Particles vibrate back and forth but do not change position
        • Most solids form crystals
          • particles form a repeating pattern
          • Ex: snow, salt, sugar, diamonds
          • Crystals break forming flat sides
        • Amorphus solids:
          • Particles do not form repeating patterns
          • Ex: Glass, Butter, Wax
    • Liquids
      • Particles close together, but free to move around
      • Allows liquids to flow
      • Viscosity: describes how fast a liquid can flow
        • High viscosity = very thick, flows slowly
          • Tar, honey, cold syrup  High Viscosity
        • Low viscosity = runny, flows quickly
          • Water, gasoline, milk  Low Viscosity
    • Gases
      • Gas have a lot of energy
        • Particles move freely in a straight line
        • Mostly empty space between particles
        • Particles change directions when they encounter obstructions (they bounce)
    • Plasma
      • Highest energy state of matter
      • Formed from intense heat or electricity ionizing gas
      • Ironically it is the most common state in the universe
      • On Earth lightning is the only natural form of plasma
    • Change of State
      • All Changes in state are physical changes
      • Solid
      • Solid to Liquid  melting point
      • Liquid to Solid  freezing point
      • Liquid
      • Liquid to Gas  evaporation point
      • Gas to Liquid  condensation point
      • Gas
      • Temp at which a liquid boils: boiling point
      SAME Temp SAME Temp
    • Special Case:
      • Sublimation: when a solid goes directly to a gas without becoming a liquid
      • Or
      • A gas becoming a solid without being a liquid
        • Examples: Frost, snow, dry ice
    • 2.4 Energy from Atoms
      • Nuclear Power
        • Most electricity in the US is produced from burning fossil fuels
        • Nuclear Power is an alternative to fossil fuels
          • Nuclear energy is produced from splitting large atoms
          • FISSION : Splitting of large atoms into smaller atoms
        • Uranium Fission
          • Uranium-235 is a fissionable isotope
          • After refining, it is placed in fuel rods to be used in power plants
          • The rods are placed in the reactor core
          • Neutrons are fired at the rods  splitting the atoms
          • A chain reaction begins
          • High amounts of heat is released
          • The heat is used to boil water  producing steam
          • The Steam turns a turbine connected to a generator = electricity
      Pgs. 54 & 55
    • Nuclear Power Plant Typical Nuclear Power Plant Design
    • 2 Points of View
      • Storing Nuclear Waste in Yucca Mountain:
        • One major problem with nuclear energy is the waste
          • Nuclear Waste: highly radioactive materials
            • Can remain radioactive for thousands of years
            • Must be stored safely
          • Yucca Mountain, Nevada
            • Selected as a possible Nuclear Waste disposal site
            • Reasons for selection: Remote, Very little rain fall, Water table very far below surface, & Land owned by US government
      • Search for Other locations:
        • Geologists have theories that water movement is very active in the area (percolation & upwelling)
          • Potentially could move toxic waste down to water table, or up to the surface
        • Earthquakes are also a concern (damaging containers)