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U2D2: Classification of MatterDo Now: 1. Look over new packets. Write your name on all papers.2. Draw a sample of a mixture of an element and a

compound.Today: 3. Book Hand out (shout out book # when asked)4. Review POGIL/Do NOW/Check3. Classification of Matter: focus on Mixtures

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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.

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Hmm….

• Is there anything in this room that would be considered matter?

MATTER

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Substances

• Are types of pure (homogeneous) matter– containing the same composition of material

throughout the sample• Cant distinguish different parts• Which is a substance?

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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.

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A. Pure Substances:

1. Elements:

Diatomic: _______________________

Monatomic: ______________________

Particle Pictures of Elements single Atom, Diatomic

ex. Fe or Rn Molecule, O2

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2. Compound: 2 or more different elements chemically combined

• CAN be DECOMPOSED into separate elements. (by chemical means)– 2 H2O 2 H2 + O2

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EXAMPLES OF COMPOUNDS Calcium Chloride: CaCl2

Sodium Chloride: NaClWater: H2O

Glucose: C6H12O6

Sucrose (table sugar): C12H22O11

Methane: CH4

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COMPOSITION OF COMPOUNDS • 2 or more DIFFERENT elements chemically

combined• Homogeneous- same throughout• Have a definite ratio

CaCl2 NaCl CH4 KNO2 1 : 2 1:1 1 : 4 1:1:2

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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

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Na: an explosive silver colored metal

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Cl2: poisonous yellow-green gas

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But Chemically combined in a Compound …

• NaCl: tasty, white colored condiment on French fries

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Whats my rule

• K• Al• Kr

• SrS• MnO2

• HCN

What about: Na2SO4, Mn

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Phases of a Pure Substances

Indicated by subscripted letter:• NaCl (s) –> (s) = ____________

• H2O (l) –> (l) = ____________

• CH4 (g) --> (g) = ____________

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MATTER

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MixturesB. Mixtures: combinations of substances that ARE NOT chemically combined togetherVariable (changeable) composition:

– a little sugar in a glass of water OR a lot of sugar in a glass of water

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Mixtures

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

Ex. _____________________________________

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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)

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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)

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b. Partssolute – ______________________________

ex:____________

solvent - ______________________________ ex. ____________

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Other Homogeneous Mixtures

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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)

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c. Types of Homogeneous Mixtures

2. Tincture: ethanol (alcohol) is the solvent: • tincture of iodine (I2)

• I2 dissolved in alcohol

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Other Homogeneous Mixtures

3. Alloy: 2 or more metals mixed togetherex. copper and zinc: ______________ ex. copper and tin: _______________ any gold (Au) less than 24K:

14K: 14 parts Au and 10 parts other metal18K: _____ parts Au and ______ parts other metal

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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

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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****

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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)

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Heterogeneous Mixtures (also called a suspension)

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b. Examples:

Sand & WaterGranite

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Heterogeneous Mixtures

Oil & Water Pizza

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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

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Colloids

• Cloudy aquarium • Whipped Cream• Mayonaise

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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

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Practice!

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

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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

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Work on Practice 2.1

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

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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)

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

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Substances; Elements

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U2D2: Properties of Mixtures; Using a Bunsen burner

Agenda:HW Collected: Vocab diagrams and 5 Q’sLab Check :need calculator and ref TableComplete Properties of MixturesHow to use the Bunsen burner!

Date Assignment Grade page

9/24 Density of Al Foil Check 249/24 How to Use a Bunsen Burner 25

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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

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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

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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

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Physical Changes: ID stays the same

• Melting• Boiling• Dissolving• Evaporating• Crushing• Stretching• Changing its shape

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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!

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Chemical Change

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Mixtures: Homogenous

• Remember, homogeneous means that it is uniform throughout the mixture.– Cant distinguish one part from

another.

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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

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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

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Whats my rule?

• Sugar (C6H12O6)

• CuSO4

• Water

• Iron• Hydrogren• Helium

• What about: FeO, Mercury

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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

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Whats my rule?

• Mud• Garbage• Chocolate chip

cookie dough

• Salt water• Kool-aid• Tap water

• What about: Iced Tea, a bag of skittles

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Rest of the period:

Continue the guided practice.

Homework for tonight:• Finish HW # 1