Today in ScienceYou will Need:1)Pencil, Colored Pencils, Highlighters or Markers2)Power Notes – Classification of Matter –Overview – 1 page 2 sides-Bookshelf

We’re

changing

seats today.

1.MANAGER– Organizing, Understanding, Turning in Work for the group

2. MATERIALS MANAGER– Collecting, Keeping supplies in good condition, Returning, Organize Table Box

3. TIMER/DESIGNER– Track and Communicate Time, In charge of design, and quality of product

4. ORAL PRESENTER– Communicator, Asks Questions for the group, Presents finding,

Check Off

Date Given

Date Due

Name of Assignment Possible Pts.

Earned Pts.

3/15 3/15Test #2 Part 1 (on-line) 95

3/16 3/16 Test #2 Part 2 (written), Extra Credit, Notes /8/20

3/19 3/22Test Corrections & Signature

40

3/19 3/23 STAR CARDS #1-30 60

3/19 3/21Power Notes – Classifications of Matter & Periodic Table - Overview

Test Retakes starting Thur. Mar. 22nd until Thur. Mar. 29th

STAR CARDSCA STATE1)Requires every 8th grader to take the STAR Science Test this year2)About 75 questions in Chemistry and Physics3)These cards will review you on concepts we’ve covered (will cover) by our testing date in late April4)Every Friday you will have a quiz on these cards.

Topic: Classification of Matter – Overview

Where have you seen things organized into groups?

ALL MATTER can be divided into ________ main categories.

6

Matter is…………………….

And can be divided into 2 categories:

Pure Substance

Mixture

-anything with mass and volume (takes up space)

-Matter w/a constant composition-All particles have the same properties

-Matter w/variable composition-Made from a blending of two or more substances

Pure Substances can be divided into two groups

Element

-made up of atoms w/same atomic #-each element has its own unique amount of protons

Examples:-Gold

-Silver

-Oxygen

-made up of atoms w/same atomic #-each element has its own unique amount of protons

Examples:-Gold

-Silver

-Oxygen

Compound-2 or more elements chemically combined-can be broken down only by chemical means

Examples:-Water – H2O-Hydrogen Peroxide – H2O2

-Ammonia – NH3

Mixtures can be divided into two types

Homogeneous Mixture

-all particles are distributed evenly-often looks like one substance

Examples:-Coffee-Kool-Aid-Cake Mix-Brass

Heterogeneous Mixture

-particles are not distributed evenly-usually can see the different “ingredients”

Examples:-Pizza-Lucky Charms Cereal-Inside of Backpack

Remember:-Pure Substances are made up of the same basic particle-Can be one type of atom or one type of molecule or compound particle

Element – atoms all the same

Compound– molecules all the same

Remember:-Mixtures: each particle keeps its own composition-Although some particles may be “hidden” they still keep their structure.

Heterogeneous- Trail Mix – different parts keep their own identity

Homogeneous - Chocolate Milk– each component keeps its own identity even though is it “blended” together

Scientists use two types of Subscripts

Subscripts (letters)

-Indicates the physical form in which the substance is found

Examples:-(s) = solid H2O(s) = ice water

-(l) = liquid H2O(l) = liquid water

-(g) = gas = H2O(g) = water vapor

-(aq) = aqueous (in solution)Nickel in liquid solution

Subscripts (numbers) -Indicates the amount of atoms needed to build the compound.

Examples:-NaCl = Sodium Chloride– -1 sodium atom , 1 chlorine atom-(table salt)

-N2O = Nitrous Oxide – -2 nitrogen atoms , 1 oxygen atom-(laughing gas)

-HC2H3O2= Acetic Acid – -4 hydrogen, 2 carbon, 2 oxygen-(main component of vinegar)

Periodic TableThe concept of elements has been around since ancient times. We now know that each element has its own unique number of protons. You can also tell the elements apart because of their different properties. However, you might notice there are more similarities between iron and silver than iron and oxygen. Could there be a way to organize the elements so you could tell at a glance which ones had similar properties? YES!

Dmitiri Mendeleev was the first scientist to created a periodic table of elements similar to the one we use today. The table showed that when the elements were ordered by increasing *atomic mass, a pattern appeared where properties of the elements repeated periodically.

*Today’s PT is ordered by increasing ATOMIC NUMBER

Protons + Neutrons

Periodic TableThe periodic table not only categorizes elements by their similar properties but helps predict the properties of new elements to be found. Today’s modern table is organized by increasing atomic number, not increasing atomic mass.

Why was the table changed?

In 1914, Henry Moseley learned you could experimentally determine the atomic number of elements. Since every element has their own unique amount of protons, this number had greater significance----so the periodic table was reorganized. Before that, the atomic numbers were just the order of elements based on increasing atomic mass.

Homework1) Complete Pgs. 1 & 2 of Overview We will be continuing with Part 2 of these Power Notes tomorrow.2) Test #2 Part 2 Corrections & Signature – Due Thursday3) STAR CARDS #1-30 – Due Friday at the beginning of class