Chemical and Physical Changes

Notes

Warm - Up What are the three states of matter?

Which state of matter is most easily compressed?

Which state(s) of matter have a definite volume?

What is the definition of a heterogeneous mixture?

ObjectiveToday I will be able to:

Describe the classification of matterDifferentiate between a chemical and physical

change

HomeworkChemical and Physical Changes WS

Wear Closed Toe Shoes Tuesday

AgendaWarm – Up

Classification of Matter Notes

Sorting Activity

Chemical and Physical Changes Notes

Sorting Activity

Chemical and Physical Changes Worksheet

Classification of Matter Review Game

Classification of Matter Review Game

The Rules5 minutes or all of the examples

One person goes at a time, in order

Classify the substance as element, compound, heterogeneous mixture or homogeneous mixture

Player may pass

I keep score

hydrogen

hydrogenelement

atmosphere

atmosphereheterogeneous mixture

sugar

sugarcompound

pitcher of Kool-Aid

pitcher of Kool-Aidhomogeneous mixture

silicon

siliconelement

lithium

lithiumelement

brass (alloy)

brass (alloy)homogeneous mixture

ocean

oceanheterogeneous mixture

salad

saladheterogeneous mixture

titanium

titaniumelement

titanium alloy

titanium alloyhomogeneous mixture

baby food (in a jar)

baby food (in a jar)homogeneous mixture or heterogeneous mixture

sodium

sodiumelement

salt

saltcompound

saline solution for contact lenses

saline solution for contact lenses

solution = homogeneous mixture

pizza

pizzaheterogeneous mixture

carbon

carbonelement

bromine

bromineelement

glass (silicon dioxide)

glass (silicon dioxide)compound

aluminum

aluminumelement

black coffee (brewed)

black coffee (brewed)homogeneous mixture

graphite

graphiteelement

(form of carbon)

water

watercompound

gold

goldelement

Lucky Charms

Lucky Charmsheterogeneous mixture

diamond

diamondelement

(form of carbon)

sulfur

sulfurelement

methane

methanecompound

blood

bloodhomogeneous mixture

milk

milkhomogeneous mixture

potassium

potassiumelement

lithium chloride

lithium chloridecompound

salad dressing

salad dressingheterogeneous mixture

air in a SCUBA tank

air in a SCUBA tankhomogeneous mixture

uranium

uraniumelement

calcium carbonate(sea shells)

calcium carbonate(sea shells)

compound

bronze

bronzehomogeneous mixture

sucrose

sucrosecompound

lead

leadelement

Chemical and Physical Changes

Notes

Physical Properties Description of a substance

undergoing a physical change

Intensive Properties – do not depend on the amount of matter present (density, boiling point, freezing point, color, odor)

Extensive Properties – depend on the amount of matter that is present (mass, volume, pressure, length)

Chemical PropertiesEnables a substance to change

into a brand new substance, and they describe how a substance reacts with other substances

Changes in Matter Through experimentation and

natural occurrences, matter tends to change in either of two ways

- Physical Changes

- Chemical Changes

Physical Changes Only physical properties change

The form of matter changes, but the identity of the matter remains the same

Examples: change in state (phase change), breaking a pencil, tearing paper

Physical ChangesPhase Change – physical

process in which one state of matter is transformed into another

Physical Changes

Physical ChangesDuring a change of state, the

temperature remains constant, but energy must be continually transferred because the particles that make up the sample have different quantities of potential energy before and after the change

Physical Changes

Chemical Changes Properties of original substance disappear as

new substances with different properties are formed

Change in chemical composition

Cannot return to original form

Can be detected through – energy changes (temperature), change in color, emission of gas, solid formed

Examples – wood burning, iron rusting, sour milk

Examples – Chemical or Physical Change?

A match lights when struck

Wood is placed into a chipper

A lump of gold is pounded into a large, thin sheet

Baking powder bubbles and gives off CO2 when it is moistened

A pan of water boils on the stove

Hydrogen Sulfide gas causes silver to tarnish

Reactions Involving Energy

Most chemical reactions, physical changes of state, and dissolving processes involve energy changes

Energy can be released or absorbed

Exothermic Reactions

Endothermic Reactions

Reactions Involving Energy

Exothermic Reactions – reactions that release energy into their surroundings

- Results in a temperature increase

- Feels warm to the touchExample Reaction – Combustion of

Propane

- C3H8(g) + 5 O2(g) 3 CO2(g) + 4 H2O(g) + 2043 kJ

Reactions Involving Energy

Endothermic Reactions - reactions that absorb energy from their surroundings

- Results in a temperature decrease

- Feels cold to the touch Example Reaction – Photosynthesis

- Sunlight + 6 CO2(g) + H2O(l) C6H12O6(aq) + 6 O2(g)

Exit TicketWrite down an original example of:

A heterogeneous mixtureA homogeneous mixtureA compoundAn element