Classification of Matter

Review

physicalphysical changechange: the chemical composition (makeup or parts) of the matter stays the same. Ex: state changes (solid to liquid to

gas), changing shape (ripping, squishing)

Review

chemicalchemical changechange: a compound’s chemical composition (makeup) is changed – it becomes a new substance ex: burning, rusting, reacting

MATTERMATTER

MixtureMixture PurePureSubstanceSubstance

HomogeneousHomogeneousMixtureMixture

HeterogeneousHeterogeneousMixtureMixture

CompoundCompound ElementElement

AtomAtom

Physically

separated

Chemicallyseparated

Can’t beseparated

mattermatter: has volume (takes up space), and mass can be solid, liquid or gas

mixturemixture: several different substances NOT chemically combined, can be physically separated into pure substances homogeneoushomogeneous: evenly mixed (solution)

ex: salt water, air heterogeneousheterogeneous: not evenly mixed

ex: sand, soup

AIR

pure substancepure substance: constant (same) composition (homogeneous), ex: water H2O or lead Pb compound or an element

compoundcompound: chemically bonded elements ex: CO2

Compound

elementelement: can not be separated physically or chemically, made of a single kind of atom

atomatom: smallest particles of an element, can not be chemically separated

Element

ELEMENTELEMENT COMPOUNDCOMPOUND MIXTUREMIXTURE

MOLECULESMOLECULES

MonMonatomicatomic DiDiatomicatomic

ex: noble gases: He, NE, Ar, Kr… Ex: halogens: F2, Cl2, Br2, H2

What classification of matter? (from the flow chart)a) Matter that can be physically separated

and is uniform (evenly mixed). b) Matter that can not be physically

separated. c) Matter that can not be physically

separated and can not be decomposed (broken apart) by chemical means.

d) Matter that can be physically separated.

e) Matter that can be physically separated but does not have a uniform (evenly mixed) composition.

f) Matter that can not be physically separated but can be decomposed (broken down) by chemical means.

g) Can an element be broken down chemically?

h) How is a mixture different from a pure substance?

i) How is an element different from a compound?

Element or compound?a) neonb) sodium bichloratec) silverd) potassium chloridee) carbon dioxidef) helium

An unknown silvery powder has a constant melting point and does not chemically or physically separate into other substances. The unknown substance can be classified as –A. an elementB. a compoundC. a mixtureD. an alloy (a homogenous mixture of metals)

A student examines a sample of matter and finds that she can’t separate it into its parts physically or chemically. This matter is:a. an elementb. a homogeneous mixturec. a heterogeneous mixtured. a gas

One example of a pure substance is:a. paperb. cookie doughc. rocks and sandd. water

Is separating a mixture a chemical Is separating a mixture a chemical process or a physical process?process or a physical process?

Separating a mixture

solventsolvent: the part of a solution doing the dissolving (the liquid)

solutesolute: a substance being dissolved in a liquid

solutionsolution: the mixture of a solvent and a solute

SOLUTESOLUTE

SOLVENTSOLVENTSOLUTIONSOLUTIONSOLUTIONSOLUTION

solublesoluble: dissolves in a solvent insolubleinsoluble: does not dissolve

Salt and water?

filtrationfiltration: insoluble solute not dissolved in a solvent Ex: sand and water

evaporationevaporation: solute can not evaporate, but solvent can ex: water and sand; water and salt

http://www.youtube.com/watch?v=NkW8MQRq82w

distillationdistillation: separation of a mixture of liquids that evaporate at different temperatures, by evaporating, condensing and collecting each liquid.

Distillation

chromatographychromatography: Mixture of solids of different masses floating in a liquid.

Lighter solids move farther and faster! Ex: ink, DNA

Experiment What color is black ink? Is ink a mixture or pure substance? How could we find out?

What method would you use…

a) to separate sand from water?b) to separate two kinds of paint

mixed with one another?c) to separate gasoline from water?d) to separate salt from water?

With your group

Write the following words and phrases, one per index card, neatly!

solid liquid gas temperature kinetic theory evaporation condensation filtration

melting freezing sublimation deposition solvent solute solution distillation

matter compound element homogeneous

mixture heterogeneous

mixture chromatograph

y

Experiment What color is black ink? Is ink a mixture or pure substance? How could we find out?

In your group

1. Mix up the cards and stack them face down.2. Choose one person to draw first. That

person picks up the top card.3. They draw on the whiteboard until a group

member guesses the word or phrase on their card. No letters or words may be drawn!

4. The correct guesser earns one point.5. Then, group member 2 chooses a card and

draws.6. Continue taking turns.

Homework

Week 5 Homework p. 1-3