• EIGHTH GRADE "B" TASKS - CHEMISTRY INTRO
     
     
     

     

    Task B-1                   9-30`

    All matter is made of atoms, also called elements.

    Elements can combine to form molecules.

    Compound - molecule made of more than one element

    PUT A "C" OR "M"

    CO2       H20       NO    O2    O3   NH3

     

     TASK B-2       10-1

    Place a check if true
                Molecules free to move?  Molecules close together?
     
    Solid
     
    Liquid
     
    Gas
     
    Plasma
     
    What is it called...
     
    solid to liquid =
    liquid to gas = 
    gas to liquid = 
    gas to solid =
    solid to gas =
     
     
     
    TASK B-3        10-2
    Changes to matter are either chemical or physical.
     
    It is sometimes difficult to tell which is which.
     
    Chemical changes mean new substances were created.
     
    Common chemical changes are:  (write examples after...)
     
    combustion (burning)
     rusting (oxidation)
     acid/base reactions
     baking 
     cooking (but not heating)
     metabolism
     
     
     Changing phase of matter is physical, ie melting.
      
     
     
     
    TASK B-4        10-3

    Mixture - different elements and

    compounds found in the same place,

    but not bound together.

    Mixures have a "mix" of properties.

     Tell me if it is an element, molecule, compound or mixture... 

    1.  O2?
    2.  CO2?
    3.  Steel?
    4. A salad?
    5. Air?
     
     
     
     
     
    Task B-5       10-4
     
    Temperature is the average amount of heat energy.
    Heat energy is motion (vibration) of molecules.

    Thermal expansion is objects getting bigger because of heat.

    Heat ALWAYS flows from more to less.

    fly  

     

     
     
     
     
    TASK B-6          10-7
    Both chemical and physical changes
    can make the substance look different.
    Chemical changes are ALSO physical changes.
     
    1.  What is metabolism?
    2.  Is metabolism a physical or chemical change?
     
     
     Classify as a physical (P) or chemical (C) change:
     
    decomposition
     
    salt in water
     
    copper turning green
     
    diamonds scratching glass
     
    water evaporating
     
    a can being crushed
     
    respiration
     
    photosynthesis
     
    Task B-7   10-8
     
    Homogeneous  - mixture that is the same throughout Ex steel
     
    Heterogeneous- mixture that is different throughout Ex. salad

     

    Solution - two evenly mixed materials. 

    You can't see the two parts, it can be a solid (steel),

    liquid (salt water) or a gas (atmosphere).

     

     

    fly
     
     

    Task B-8   10-9

    Open system - matter moves in and out

    closed system - no matter moving in or out
     
    Matter does not appear or disappear,
    no matter is gained or lost in reactions 
     
    Conservation of mass - all the atoms that go into a reaction
    have to come out.
     
     
     
    Task B-9  10-10
     
     Atoms are neutral because they have the
     same number of protons and electrons.
     
    A chemical symbol has a capital letter,
    and sometimes a lower-case letter.
    Oxygen = O

    1.  How many protons does oxygen have (top number)?

    2.  How many electrons does oxygen have?

    3.  How many neutrons do most oxygen atoms have

           (subtract top number from bottom number)?

     

      
     
    Task B-10     10-11
    Protons and neutrons make up the nucleus, at center.
    Electrons are found "orbiting" outside the nucleus.
     
    The atomic mass is the protons added to neutrons.
    Both protons and neutrons count for 1.
     
    1.  How many neutrons are in most carbon atoms?
     
    fly
     
     
     
     
     Task B-11     10-15
     
    Isotopes = atoms with different number of neutrons.

    The atomic mass is an average of the isotopes found in nature.

    1.  How many protons are in Li (lithium)? 
     
    2.  How many neutrons are in Li? 
     
    3.  How many e-?
     
    4.  Now do Fluorine:    p+         e-        n=
     
     
     Task B-12   10-16 
    The periodic table lists all the atoms in our universe.
    Periods - Go ACROSS - share energy level
    Groups (families) - Go DOWN - same numbers of valence electrons
     
    Valence electrons - electrons found in outer energy level 
     
    1.  Write the symbols for all the elements in period 1.
    2.  Write the symbols for all the elements in group 1.
    3.  BORON:   p+       e-       n=
     
     
    Task B-13               10-17
    Electrons (e-) are found in different "shells" (energy levels)
    outside the nucleus.

    The first shell holds 2 electrons.

    The next two shells hold 8 electrons each.

    1. How many elements are in period 1?

    2. How many electrons can the first energy level hold?

    3.  How many p+, e-, and n= are in Li? 
    4.  Where is the mistake in the table?

     

     
     fly
     
     
     

    DOT diagram shows the number of valence electrons.

    Make a dot diagram for every element in period 1 and 2. 

    1. How many valence electrons does each element of group 2 have? 
     
     
     
    dot

     

     
    Task B-14    10-18
    Valence e- are the only e- that are involved in chemical reactions.

    All atoms want a full outer energy level (shell).

    Every new period starts a new energy level (shell).

    GROUPS show the number of valence e-.

    List                      O          Na

    1.                 p+_____    _____

    2.                 e- _____    ______

    3.                 n= _____    ______
     
    4.  valence e- = _____    ______
     
     
     
     
     

     
     
     
     
     
     
    TASK B-15      10-21
     
    Ions are atoms with a charge.
    An ion has a different number of protons and electrons.
    Protons are positive, electrons are negative.
    Add them, that is the charge.
     
    1. What charge would an ion have if it had 6 protons and 5 electrons?
    2. What charge would an ion have if it had 6 protons and 7 electrons?
    3.  What element has 6 p+?
     
     
     
    TASK B-16   10-22
     
    John Dalton came up with atomic theory that elements
    are individual atoms that are identical. 
     
    1.  How can you tell a chemical change from a physical change?
     
    2.  How can you tell an open system from a closed system?
     
    3. Who came up with the modern idea of an atom?
     

      CC Atomic Theory

     
     

    Task B-17     10-23

    A MOLE is 6.022×1023 atoms or molecules.  

    It converts mass into the number of particles.

    2 Hydrogen + 1 Oxygen = 1 H2O

    Metals lose electrons, non-metals gain electrons. 

    Water allows electrons to transfer.

    The charge is written on the top right corner of the symbol.

    1.     If Li loses an e-, what charge will it have?

    2.     How many ve- will Li+ have?

    3.    If F gained an e- what charge would it have?

    4.   How many ve- will F- have?

     

    Moles

     

     
     
    Task B-18  10-24
     Metals on left - metals conduct heat and electricity
    Non-metals on right - They don't conduct heat and electricity.
    Metalloids- have some properties of metals, some non-metals.
    Noble gasses - group 18, have full energy level of Ve-.
    Noble gasses don't usually make chemical bonds.
     
    1.  Why are the masses decimals on PT? 
     
    2.  How many in Al, Cl? 
    p+ =  

    n= = 

    e- =
    ve- =  
     
     
     
     
     
    TASK B-19      10-25

    Combustion (burning, fire) is a chemical change

    that occurs when oxygen (O) atoms attach

    to (usually) carbon making CO2 and releasing heat.

    Fire needs: fuel, oxygen, and heat 

    There are over 366,000 house fires each year.

    Smoking is the number one cause of house fires.

     

    1.  Where will you meet your family in the event of a fire?

    2.  Where is there a fire extinguisher in your house?

     
    fly
     

     Task B-20            10-28

    All atoms want a full outer energy level of electrons. 

    An ionic bond is made when oppositely charged atoms attract.
     
    A metal bonds with a non-metal and makes a salt.
     
    Add positives and negatives to get charge.
     
    1.  What is the charge of 6p+ and 7e-?
     
    2.   What is the charge of 8p+ and 7e-?
     
    3.  What is the charge of 4p+ and 7e-? 
     

     

    TASK B-21    10-29

    Mendeleev created the first periodic table in 1869 

    by arranging the elements by increasing mass.

     
    1.  Who created the first periodic table?
     
    2.  Who came up with the modern idea of an atom?
     
    3.  How is today's PT arranged?  The atomic number goes up...

     

     
     Draw a dot diagram of Na and Cl
     
     

    TaSK B-22              10-30

    A subscript is the number below and to the the right of a symbol.

    It tells how many of that atom is in the molecule.

     

    A coefficient is the number before a symbol or molecule.

    It tells how many in the reaction.

    Circle the coefficient, underline the subscripts.

    2H2 + O2 → 2H2O

    1.  How many H atoms?

    2.  How many O atoms?

    3.  Why are there the same number on both sides?

     

    Make a dot diagram of Li and S.

     

    fly

     

    TASK B-23      11-4

    Reactants on left.  Yields:  Products on right.
    CaC2 + 2 H2O2 → C2H2 (acetylene)+ Ca(OH)2 + O2

    The charges must balance in an ionic bond.

    First, draw a dot diagram of Mg and F.

    1.  What is an ionic bond?

    2.  How many valence e- does Mg have?

    3.  How many e- will Mg lose in water?

    4.  What charge will Mg have after it lost e-?

    5.  How many F will it take to balance the charge of one Mg?

     

     

    Task B-24       11-6

    Metals are solid, shiny, malleable, ductile,

    and good conductors of heat and electricity.

    Non-metals are usually gasses and are reactive,

    dull, brittle, and poor conductors.

    The noble gases, group 18, do not normally form chemical bonds.

    Groups share properties.

    1.  Name two noble gases.

    2.  What metals do we use to conduct electricity?

    3.  How many Li will form an ionic bond with one O?(draw dots)

    4.  Why don't noble gases form bonds?

     

     

    TASK B-25          11-7
     
     
    Metalloids have both metal and non-metal properties.
     
    1.  Draw the dot structure of Be and Cl, then draw an ionic bond.
    2.  What is the ratio of Be to Cl?  Write the equation.
    3.  What types of elements are always found in an ionic bond?

     

     

     

     
     

     TASK B-26        11-8

    Draw the dot diagram and equation for:

    Be + F

    Mg + O

    Circle the reactants, underline the products. 

    1.  What is the Conservation of Mass?

    IONIC BOND

     

     

    TASK B-27       11-12

     1.   What is the number in front of a formula called?

    2.  What is the small number after an element called?

    3.  What is an ionic bond?

    4.  How many K do you need to ionically bond with N?

    Draw dot diagram and equation

     

     

    Task B-28               11-14

    A covalent bond is when the electrons

    are shared between two atoms.

    Both atoms count the ve- for their outer

    energy level to be full.

    Non-metals make covalent bonds.

    1.  Draw a dot diagram for H2O in a covalent bond.

     2.  Draw a dot diagram for CO2.

     fly

    Water video CC

    fly  

     

    In 2010, more than 76,000 America's veterans experienced

    homelessness on a given night in January, according to the U.S. Dept. of Veterans Affairs.

    The estimated number of homeless veterans dropped from more than 74,000 individuals in 2010 to fewer than 40,000 in 2016.

     

    About 11% of the adult homeless population are veterans.

     

    1 in 8 veterans are unemployed (NPR, 11-11-11)

    A recent RAND Corporation study titled “Invisible Wounds: Mental Health and Cognitive Care Needs of America’s Returning Veterans” found that an estimated 1 out of 5 of all service members and veterans suffer from PTSD or some form of major depression.

     

     

     

     

     

    Task B-29                11-15  

    Draw dot diagram and write the equation for 

    Na + O                  C + H                 O + F

    1.  How can you tell if it is an ionic or covalent bond?

     

     
     
     
    Task B-27       11-18
     
     
     
     
     
     
     
     
    EL  
     
      
     

    TASK B-28        11-12 

     

    Draw Be + Cl     and    N + H

     

     

     
     
     
     
     
     
     
     
     
     
     
     
     
    1.   What period is Na, Ar?  
     
     
    2.    How many valence e-? in Na, Ar?
     
     
     
    3.   What group is Na, Ar? 
     
     
    4.   How many energy levels does Na, Ar have?
     

    Task B-11     10-18

    Quiz is tomorrow! 
     
     
    1.  What is the difference between a mixture and a compound?
     
     
    2   How many electrons in Cl?
     
     
     
    3.   How many valence electrons are in Cl?
     

     

     

     
     Task B-20       11-9
     

     

     

     TASK B-21    11-12

    Metals are hard, shiny, malleable (flat sheet) and ductile (wires). 
     
    Metals conduct heat and electricity.
     
    Alloys are mixes of different metals,
    steel is iron mixed with carbon and other metals.
     
    1.  Name all the metals you can think of.
     
     
    Task B-22      11-13
    Non-metals make ceramic and glass. 
    They are insulators, they DO NOT conduct heat and electricity.
     
    Metalloids have both metal and non-metal properties. 
     
    The NOBEL gases (group 18) all have a full valence e-,
    so they do not react with other elements usually. 
     

    TASK B-23      11-16

     

     
    All quizzes must be retaken before Thanksgiving break.
     
    1.  How many valence e- does Mg have?
     
     
    2.  How many valence e- does Cl have? 

     

     
     
    TASK B-25    11-18

     

     

     

    TASK B-8      10-30

    After the quiz, log on to Powerschool

    and make sure your grade is correct.

    1.  What is the difference between an

    element, a molecule, and a compound?

     

    Task B-9    11-3

    CaC2 + 2 H2O → C2H2 (acetylene)+ Ca(OH)2

     

    In the Mass Conservation lab matter seemed to disappear...
    1.  Where did the matter go?
    2.  Was it an open or closed system?`

     

     

     

     

     

     

     Task B-10       11-6

     

     

    http://www.nfpa.org/~/media/Files/Research/Fact%20sheets/homesfactsheet.pdf

     

     

    Takeaway:

    Where does the mass of the candle go when it is burned (combustion)?

     

     

     

     

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

     

    http://www.quia.com/quiz/303980.html?AP_rand=749225156

     

    http://www.mcwdn.org/chemist/pcchangequiz/pcchangequiz.html`

     

    http://mint.ua.edu/games/chemical-mixup/

     

    TASK B-12     11-10

     

     

     

     

     

     

     

    TASK B-13

    An ion is an atom with a charge.

    A charge comes from a different number of protons and electrons.

    Oppositely charged ions attract.

    Water allows electrons to transfer, then an ionic bond

    is made when the metal bonds to a non-metal.

    1.  What will be the charge of the elements from group 1?

    2.  Group 16?

     

     

    http://thinkprogress.org/economy/2013/10/29/2850751/food-stamps-cut-veterans/

     

     

     Task B-14           11-12

    In an ionic bond, the charges must balance.

    The charge will be the subscript of the other atom. 

    1.  What is the charge of Na in water?

    2.  In what ratio will Mg+2  bond with Cl-?

     

     Tutorial on Ionic Bonds  Click and change the groups, ie alkali metals

     

    Ionic charges tutorial

     

     Ionic Bonding Practice

     

    Test your skills!

     

    TASK B15      11-13

     

    covalent 

     

    dot-structures-of-covalent-compounds

     

     

     

     Task B-16      11-17

    A covalent bond is when an electron is_________ between atoms.

    The electrons count for both atoms.

    Covalent bonds usually form in non-metals.

    Covalent bonds make molecular compounds.

    Examples:  H20         CO2               C6H12O6

    Draw a dot diagram for water, H20,  and carbon dioxide, CO2.

     

     

     

     

     

    http://www.ck12.org/book/CK-12-Physical-Science-Concepts-For-Middle-School/r7/section/2.50/

    read everything, you may watch the youtube video at the end, try to answer the questions

     

    http://www.kentchemistry.com/links/AtomicStructure/lewis%20Dots.htm

     

     

     http://www.sciencegeek.net/Chemistry/taters/Unit3ValenceElectrons.htm

     

    Task B-17     11-18

    Quiz Friday for Chapter 1

    A covalent compound does NOT conduct electricity in water.

    Ionic compounds DO conduct electricity in water.

    Ions provide the path for the electrons to move through the water.

     

    1.  How can you tell if a substance is ionic or covalent?

     

    Task B-18       11-19

    A covalent bond that shares the electrons unequally is polar.

    The molecule has a positive and negative side.

    The opposite charges are slightly attracted.

    1.  Why is an ionic bond made between a metal and a nonmetal?

    2.  Why are covalent bonds made between nonmetals?

     

    polar 

     

    polar 

     

    covalent_bonding_of water

     

    ionic ratio practice

     

    Chem bonding quiz

     

     

     Task B-19    11-20

    1.  Draw Mg+2 + Cl

    2.  Draw C + O2

     

    TASK B-20       11-21

    Only copy your answer!

    Did you:

    1.  Study for a small period of time for several days?

    2.  Study a lot a night or two before the test?

    3.  Study only a little?

    4.  Didn't study at all?

     

     Task B-21     12-1

    1.  What is the most e- for period 1 elements?

    2.  What is the most valence e- for period 3 elements?

    3.  Use one word to describe ionic bonds, one for covalent.

     

     

     TASK B-22    12-2

    1.  Draw Mg+2 + Cl-   (ionic)

    2.  Draw 2O (covalent)

    3.  Draw C + 2O (covalent)

     

     TASK B-23

    Chapter 1 test is tuesday.

    1.  Draw H2O

    2.  Draw ___Na + O

     

    Trial Quiz on Bonding

     

     

     

     

     

     

     

     

     

     

     

     

    End of current Tasks

     

     

     

     

     

     

     

     

    https://docs.google.com/a/pgsd.org/document/d/1DwG_3w2O5PC4dizUDxfIh7CFKG7gF_R3SJNar91wyRk/edit?usp=sharing

    TASK B-19

    How many protons, neutrons, and valence electrons are in carbon (C)?

    What period and group is C in?

     

     

    http://www.glencoe.com/sites/common_assets/science/virtual_labs/E20/E20.html

    http://www.saburchill.com/chemistry/chapters/chap006.html

    http://www.saburchill.com/chemistry/visual/PT/001.htm

     

    Takeaway:

    What are valence electrons and why do elements in the same group have the same number?

     

    TASK B-20

    Atoms are neutral because they have the same number of protons and electrons.

    If there is a different number of electrons than protons, it is an ion.

    Ions are charged atoms.

    1.  How would you make a positive ion?

    2.  How would you make a negative ion?

    Takeaway:

    What are valence electrons and why do elements in the same group have the same number?

     

     

     

    GREAT REVIEW OF PERIODIC TABLE AND VALENCE ELECTRONS:

     

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

     

     

     

     

    Task B-21

    How many protons, neutrons, and electrons and valence electrons are in Mg?  S?

    26% of homeless population are veterans.*

    33% of male homeless population are veterans (NCHV)

    In 2010, more than 76,000 America's veterans experienced

    homelessness on a given night in January, according to the U.S. Dept. of Veterans Affairs.

    1 in 8 veterans are unemployed (NPR, 11-11-11)

    A recent RAND Corporation study titled “Invisible Wounds: Mental Health and Cognitive Care Needs of America’s Returning Veterans” found that an estimated 1 out of 5 of all service members and veterans suffer from PTSD or some form of major depression.

     

    http://thinkprogress.org/economy/2013/10/29/2850751/food-stamps-cut-veterans/

     

     

    Task B-22

    https://docs.google.com/a/pgsd.org/document/d/1DwG_3w2O5PC4dizUDxfIh7CFKG7gF_R3SJNar91wyRk/edit?usp=sharing

     

    Ionic Bonding Practice

    http://www.learner.org/interactives/periodic/groups_interactive.html

    Great Video on Ionic Formula

     

     

    Task B-23

    Oppositely charged ions attract.

    Water allows electrons to transfer, then an ionic bond is made when the metal bonds to a non-metal.

    What will be the charge of the elements from group 1?  Group 16?

     

    Task B-24

    Ionic bonds make crystals.

    The crystals dissolve in water turning into ions.

    When the water evaporates, the crystals are left behind.

    1.  What would be the formula if Na atoms make a crystal with one Cl atom?

    2.  Mg and Cl?

     

     

    Takeaway:  What is happening when table salt makes a bond and crystalizes?

     

     

     

     

    Dot Structure

     

     

    Tutorial on Ionic Bonds

     

    chemical change quiz

     

    ionic charges tutorial

     

     

    Ionic Charges 2

     

    Ionic Bonding Practice

     

    Great Video on Ionic Formula

     

    TASK B-25

    Does H2O conduct electricity?

    Ionic compounds conduct electricity in water because the crystal dissolves into ions.

     

     

    Task B-26

     A covalent bond is when an electron is shared between atoms.

    The electrons count for both atoms.

    Covalent bonds usually form in non-metals.

    Covalent bonds make molecular compounds.

    Examples:  H20         CO2               C6H12O6

    Draw a dot diagram for water and carbon dioxide.

     

    Takeaway:  What is happening when table salt makes a bond and crystallizes?

     

    Task B-27

    A covalent compound does NOT conduct electricity in water.  Ionic compounds DO conduct electricity in water.

    Ions provide the path for the electrons to move through the water.

     

    How can you tell if a substance is ionic or covalent?

     

     

    Takeaway:  What is happening when table salt makes a bond and crystallizes?

     

     

    Task B-28

    You will be performing a lab, all safety equipment will be worn at all times needed or you will be sent to time-out!

    Lab report will be due 11-22.  30 points off for lateness.

    Covalent quiz will include dot diagrams, Friday.

     

     

    I teach a simplified version of electron configuration. Here is a more complex model.

     

     Task B-29

    Covalent bonds can be polar.

    Polar molecules have a + and a - side, like magnets.

    Surface tension is due to polar bonds in water.

    Non-polar bonds mean the electrons are shared equally.

     

     

     

     

      CRISS CROSS DOT STRUCTURE

     

     

     COVALENT BONDING IN HYDROGEN

     

    COVALENT BOND IN WATER

    BONDING QUIZ

    C

     

     

     

     Task B-30

    The electrons that are shared in a covalent bond are always between the bonded atoms.

    Draw two nitrogen atoms bonding.

    Is it a polar molecule?