Draw this model now

elements, mixtures, compounds video:

This is a model of what? What are the red objects? (label it now) What is the name of the blue region? What two objects make up the blue region?

Everything that exists is made of matter (even the air you now breathe). So, what is matter? Matter is anything which has both mass and volume. Are ideas matter? Matter is made of atoms which can be arranged in almost infinite ways to make the world as we know it (brick houses?) Atoms are on the order of a trillionth of a meter in size: meters Atoms are constantly moving in irregular-jerky like motion called Brownian motion (model?) So, though you may have a solid material, in fact at the atomic level atoms are moving quite vigorously but you cannot see/feel the motion!

I. Element (ie: oxygen, hydrogen, lead, gold, krypton): A. exists as only one type of atom: it is, therefore a pure substance (This does not often occur in nature); gold necklace? Oxygen is the most common pure element on Earth (occurs as a dioxide: O 2, what does “di” mean?) B. cannot be broken down by chemical reactions: burning/acids/eating (but nuclear rxns: yes!) C. There are some 118 elements (this # changes as we discover new elements), 90 of these are naturally occurring, 22 are synthetic (?) D. two large groupings: metals and nonmetals ( which is the larger group?)

E. they can ALL occur as different energy states: solid, liquid, gas or plasma: gold  gas? F. symbology: 1. abbreviated by a unique letter which is capitalized, if there is a second letter it is lower case: Cu oxygen = O hydrogen = H helium = He lead = Pb (?) gold = Au (?) NOTE: Latin is the basis for the symbol: dead language thus it does not change: world-wide use

What element is this and what is the easiest way to find it on the periodic table? Draw this now:

2. the atomic number defines the element: it is unique: no other element has that number! (like DNA is to the living) 3. the atomic # also identifies the number of protons per atom (located in the nucleus). So, atomic # = # protons per atom G. each element has its own physical and chemical properties: called its own characteristic properties, thus these characteristics properties can be used to identify and separate elements, such as the temperature of a phase change to separate water from alcohol (distillation) or as a forensic scientist?

2. Mixture (ie: ocean, air, lemonade): A. two or more physically combined substances (elements and/or compounds): NOT chemically combined! Thus, there are no bonds between substances: salt & pepper B. not a pure substance (pure substance cannot be separated by physical means) C. their individual substances retain their own characteristic properties, thus can use their c.p. to separate them: tap water, air? D. use physical means to separate mixture: filter, dehydrate (salt water), density, sort (salt & pepper) E. two types of mixtures: 1. homogeneous mixture: equal distribution of each substance (sugar cookie): lemonade? 2. heterogeneous mixture: unequal distribution of each substance (chocolate chip cookie): lemonade?

Mixture of colors:

Mixture or compound? Homo or heterogeneous?

3. Compound (ie: water, wood, most of what is around us!) A. most individual atoms of elements are unstable (reactive: like freshmen!), and thus want to chemically combine to form stable new substances (like seniors are) by creating: chemical bonds (ie: magnets?) B. the new substance has new and different characteristic properties: H 2 O, NaCl, MgCl? C. atoms always combine in definite proportions: this is called a chemical formula: 1. 3H 2 O ? 2. tells the # of molecules (3) and # of atoms (9) 3. coefficient = # molecules: three H 2 O molecules: H 2 O + H 2 O + H 2 O 4. subscript (sub ?) = # atoms of only that atom: H 2 = two hydrogen atoms 3H 2 = 6 atoms

Compound of table salt (NaCl):

D. two groups of compounds, based on how they combine: 1. molecular: atoms share electrons, ie: H 2 O 2. ionic: atoms gain or lose electrons, becoming a “charged atom”: *gain e - and become negative (anion) *lose e - and become positive (cation) a. most are solids and soluble in water b. ie: NaCl (table salt)