physical & chemical properties & physical & chemical changes

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P/C P/C Physical & Chemical Properties & Physical & Chemical Changes

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Page 1: Physical & Chemical Properties & Physical & Chemical Changes

P/C P/C

Physical & Chemical Properties&Physical & Chemical Changes

Page 2: Physical & Chemical Properties & Physical & Chemical Changes

Physical Properties

Identification Examples Usually a measurable

characteristic you can observe without changing the chemical formula or composition such as

Density (universal p.p.) Size/Shape Color Temperature of phase changes

Melting point, boiling point, freezing point, condensation point

State of matter, Texture, Hardness, Odor, Conductivity, etc.

Physical Properties of Water Density = 1.0 g/mL Clear Liquid Boils & Condenses @ 100°C Freezes & Melts @ 0°C

Physical Properties of Alcohol Density = .789 g/mL, clear, liquid,

BP/CP = 80°C, MP/FP = -114°C

Physical Properties of Iron Solid, metallic, responds to a

magnet, conducts electricity, melts @1535°C, boils @ 2750°C, etc.

Page 3: Physical & Chemical Properties & Physical & Chemical Changes

Physical Changes

Identification Examples A change in appearance

(size, shape, state) without a change in the composition (chemical make up)

Tearing/Breaking Dissolving Phase changes (boiling,

evaporating, condensing, sublimating, depositing, melting, freezing (solidifying)

Physical Changes in Water Water freezes to form ice Breaking an icicle Boiling water

Physical Changes in Alcohol Evaporates quickly

Physical Changes in Iron Melting iron to pour in a

mold. Magnetizing an iron bar with

a blow or electromagnet.

Page 4: Physical & Chemical Properties & Physical & Chemical Changes

Chemical Properties

Identification Examples The ability to react with

other substances Doesn’t mean it has

changed but that it could in the right conditions

Must have been observed reacting in the past to know this

Flammability Corrosivity Toxicity (poisonous) pH Reactvity

Chemical Properties of Water Ability to react with metals to

from bases/corrosion Ability to react with

nonmetals to form acids

Chemical Properties of Alcohol Flammable (ability to burn) Toxic in moderate quantities

Chemical Properties of Iron Ability to rust.

Page 5: Physical & Chemical Properties & Physical & Chemical Changes

Chemical Changes

Identification Examples A reaction where new

(different) substances are formed

Can be written as a chemical equation

Evidence a Chemical Change occurs Change in color (without dyes) Change in odor Gas is produced (no heat added) Solids forming from liquids

(precipitate) Spontaneous change in

temperature (no heat added) Light is produced

Chemical Changes in Water Hydrolysis separates water

into hydrogen & Oxygen Water reacting with sodium to

form Sodium Hydroxide and hydrogen gas

Chemical Changes in Alcohol Alcohol burning to form CO2

and H2O and heat

Chemical Changes in Iron Iron combining with oxygen to

from rust (Fe2O3)

Page 6: Physical & Chemical Properties & Physical & Chemical Changes

Identification Time

Identify each of the following as either a Physical Property, Physical Change, Chemical Property or a Chemical Change: The color of the desktops are green Zinc has the ability to corrode when wet Moriah broke her bumper when she hit a

deer The food I eat is converted into waste

Page 7: Physical & Chemical Properties & Physical & Chemical Changes

Check your lab data & notes Does a spontaneous change in temperature

indicate a physical or chemical change? Which experiments resulted in a temperature change? Which ones were chemical? Physical? Why?

Does a spontaneous change in color indicate a physical or chemical change? Which experiments resulted in a color change? Which ones were chemical? Physical? Why

Does a spontaneous production of gas (bubbling) indicate a physical or chemical change? Which experiments resulted in gas production? Which ones were chemical? Physical? Why?

Page 8: Physical & Chemical Properties & Physical & Chemical Changes

Compare/Contrast

Physical v. Chemical Property v. Change