U2D2: Classification of Matter Do Now: Look over new packets. Write your name on all papers. Draw a sample of a mixture of an element and a compound. Today: Book Hand out (shout out book # when asked) Review POGIL/Do NOW/Check 3. Classification of Matter: focus on Mixtures

U2D1:MATTER!!! Chemistry is all about the study of matter, the changes it undergoes and the energy associated with these changes. Matter is simply anything that has a definite mass and volume.

Hmm…. Is there anything in this room that would be considered matter?

MATTER

Substances Are types of pure (homogeneous) matter containing the same composition of material throughout the sample Cant distinguish different parts Which is a substance?

1. Elements: cannot be decomposed by chemical change. A. Pure Substances: Have a fixed composition: H2O is ALWAYS 2-H and 1-O 1. Elements: cannot be decomposed by chemical change. They are made up of 1 type of atom All atoms have the same element have the same atomic # (# of protons) Symbols 1 capital letter : O, N, C 2 letters, the first of which is capitalized, the second lower-case: Ni, Fe, Li, Xe.

Diatomic: _______________________ Monatomic: ______________________ Pure Substances: 1. Elements: Diatomic: _______________________ Monatomic: ______________________

2. Compound: 2 or more different elements chemically combined CAN be DECOMPOSED into separate elements. (by chemical means) 2 H2O  2 H2 + O2

Examples of COMPOUNDS Calcium Chloride: CaCl2 Sodium Chloride: NaCl Water: H2O Glucose: C6H12O6 Sucrose (table sugar): C12H22O11 Methane: CH4

Composition of COMPOUNDS 2 or more DIFFERENT elements chemically combined Homogeneous- same throughout Have a definite ratio

Compounds have properties DIFFERENT from the elements which make them up Na: an explosive silver colored metal Cl2: poisonous yellow-green gas NaCl: tasty, white colored condiment on French fries

Na: an explosive silver colored metal

Cl2: poisonous yellow-green gas

But Chemically combined in a Compound … NaCl: tasty, white colored condiment on French fries

Whats my rule K Al Kr SrS MnO2 HCN What about: Na2SO4, Mn

Phases of a Pure Substances Indicated by subscripted letter:  NaCl (s) –> (s) = ____________ H2O (l) –> (l) = ____________ CH4 (g) --> (g) = ____________

MATTER

Mixtures B. Mixtures: combinations of substances that ARE NOT chemically combined together Variable (changeable) composition: a little sugar in a glass of water OR a lot of sugar in a glass of water

Mixtures Substances retain (keep) their characteristics or properties so when you separate them, you get the same substances back ex. _____________________________________

Mixtures Mixtures of the same substances may have different properties if the amount of each is different in the mixtures: Cast Iron: brittle (iron with a lot of carbon) (Cast iron pans, railings) Steel: Bendable – malleable (iron with a little carbon)

A. Homogeneous Mixture - components are uniformly distributed throughout a. Characteristics: uniform – the same throughout cannot see parts can not be separated by filtration (but can be boiled to separate)

b. Parts solute – ______________________________ ex:____________ solvent - ______________________________ ex. ____________

Other Homogeneous Mixtures

c. Types of Homogeneous Mixtures 1. Amalgam: mercury (Hg) is the solvent: Ex. silver dental fillings: silver (Ag) dissolved in Hg (Also used to mine gold (Au), bad for the environment)

c. Types of Homogeneous Mixtures 2. Tincture: ethanol (alcohol) is the solvent: tincture of iodine (I2) I2 dissolved in alcohol

Other Homogeneous Mixtures 3. Alloy: 2 or more metals mixed together ex. copper and zinc: ______________ ex. copper and tin: _______________ any gold (Au) less than 24K: 14K: 14 parts Au and 10 parts other metal 18K: _____ parts Au and ______ parts other metal

4. Aqueous solutions homogeneous mixtures with water as the solvent _______________ solutions NaCl (aq) (aq)= aqueous Sodium chloride dissolved in water Solution means a homogeneous mixture

Aqueous Solutions: ex. NaCl (aq) Recall….. solute – stuff that gets dissolved __________ solvent - stuff that does the dissolving ____________ Water is called the ____________ ___________ because it dissolves so many things well **SOLUTION MEANS HOMOGENEOUS MIXTURE****

2. Heterogeneous Mixtures : varying composition throughout a. Characteristics Particles are visible Large particles will settle out; needs to be shaken in water mixtures Can be separated by filtration (water suspensions)

Heterogeneous Mixtures (also called a suspension)

b. Examples: Granite Sand & Water

Heterogeneous Mixtures Pizza Oil & Water

Colloids Special type of heterogeneous mixture- Particles are larger than molecules but too small to see Scatter light so makes things blurry, turbid (cloudy), translucent Fog

Colloids Cloudy aquarium Whipped Cream Mayonaise

Mixture Dot Diagram See how we have 2 different things mixed together Red and blue are bound together (compound) and yellow (element) is mixed with it

Practice! MIXTURE HOMOGENEOUS HETEROGENEOUS Soil Air (clean) KCl (aq) 22 K Gold

MIXTURE HOMOGENEOUS HETEROGENEOUS Chocolate Chip Cookie NaNO3 (aq) Identify the following as HOMOGENEOUS or HETEROGENEOUS mixtures by placing a check () underneath the appropriate heading. MIXTURE HOMOGENEOUS HETEROGENEOUS Chocolate Chip Cookie NaNO3 (aq) Italian Salad Dressing Sand & water

Work on Practice 2.1

Physical vs Chemical properties Let’s Brainstorm your own Chemical and Physical properties and changes

Properties of Elements Properties do not vary: All samples of aluminum have the same density Cannot change identity or properties by PHYSICAL changes ex. Boiling, melting Can change in identity and properties by a chemical change ex. Burning (combustion), rusting (oxidizing)

Reference Table S: (Superfriends’ favorite): properties of the elements

Substances; Elements

U2D2: Properties of Mixtures; Using a Bunsen burner Agenda: HW Collected: Vocab diagrams and 5 Q’s Lab Check :need calculator and ref Table Complete Properties of Mixtures How to use the Bunsen burner! Date Assignment Grade page  9/24 Density of Al Foil Check    24 9/24 How to Use a Bunsen Burner 25

Changes of Matter They can either be physical or chemical Physical: Doesn’t Change the Identity of the matter, just its form Chemical: changes the identity of the matter

You tell me; Physical or Chemical? The paint has worn away, so the steel body of an old car begins to rust (rust forms when iron reacts with oxygen…) Chemical Potassium thiocyanate crystals dissolve easily into water. Phyiscal

You tell me; Physical or Chemical? A 10.0 g sample of lauric acid can be melted by adding heat. Physical Sodium metal explosively reacts with water to form hydrogen gas and sodium hydroxide. Chemical

Physical Changes: ID stays the same Melting Boiling Dissolving Evaporating Crushing Stretching Changing its shape

Chemical changes: ID changes Rusting (Iron reacting with oxygen) Burning (Reacting with Oxygen) Decomposing (Breaking bonds) 2 H2O  2 H2 + O2 Reacting with… X + Y  XY A new compound was made!

Chemical Change

Mixtures: Homogenous Remember, homogeneous means that it is uniform throughout the mixture. Cant distinguish one part from another.

Illustrating Types of Matter; Dot Diagrams Each dot represents a single atom. Different types of dots are different types of elements Ex; Different phases of the same element: Solid Liquid Gas

What are these dot diagrams for What are these dot diagrams for? Element Diatomic Molecule (not a compound since its only 1 type of atom). Br, I, N, Cl, H, O, F Compound (2 different elements bonded together) Heterogeneous Mixture Homogeneous Mixture

Whats my rule? Sugar (C6H12O6) CuSO4 Water Iron Hydrogren Helium What about: FeO, Mercury

Figure out what makes the 2 columns different and then classify the bottom terms Water Iron Sugar Gatorade Sugar Water Salad What about; Aluminum, cereal, coffee, oxygen

Whats my rule? Mud Garbage Chocolate chip cookie dough Salt water Kool-aid Tap water What about: Iced Tea, a bag of skittles

Rest of the period: Continue the guided practice. Homework for tonight: Finish HW # 1