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Unit 3 Outline
• Properties of Matter
• Identification of Heat and Transfer
• Classification of Matter
• Calculating Solutions
Unit 2: Properties Unit 2: Properties of Matterof Matter
Physical Property
• Physical Property – a property that can be observed without changing the matter
• Examples:– color - taste - hardness– odor - density– boiling point– melting point– malleability– ductility
• malleable – able to be flattened into a thin sheet or foil
• ductile – able to be pulled into a long thin wire
** all metals are both malleable and ductile
Two types of Physical Properties1. Extensive
-Depends on how much there is -for example: volume, mass, weight, etc…
2. Intensive-Depends on the type of matter NOT how much there is-For example: density, melting/boiling points, color (sometimes), etc…
Chemical Property• Chemical Property –
– the ability of a substance to combine with or change into another substance
– describes how a substance reacts or fails to react with other substances to produce new substances
• Examples– ability to rust or corrode– ability to react with an acid or base– ability to burn (combustion), flammability– oxidation, hydrolysis
States of Matter / Phases of Matter
State Volume Shape
Solid definite definite
Liquid definite takes shape of its container
Gas takes volume of its container
takes shape of its container
State or Phase
Particle level picture
Particles description
Keep Volume
?
Keep shape
?
Solid
Liquid
Gas
Arranged in orderly pattern Yes Yes
Touching, but not tightly packed Yes No
Far apart and rarely touching
No No
State or Phase
Particle Movement
Amount PE Amount KE Example
Solid
Liquid
Gas
Low Ice
Moderate Water
High Vapor
Vibrational only
Vibrational & translational
Move freely
Low
Moderate
High
Plasma – 4th state of matter
- an ionized gas
Physical and Chemical Changes
Does the chemical make-up of the substance actually change?
Changes that can occur to matter
Physical• a change that doesn’t
alter the composition of a substance– Examples: Cut, crumple,
tear, split, bend, crush, grind, and rip
Chemical• an alteration of the
chemical composition of a substance that results in the formation of a new substance
• ALWAYS forms a new substance that has different physical and chemical properties than the original substance.
• Also known as a chemical reaction.
Evidence of a Chemical Change
• change of color (unexpected)• change of odor• production of a gas (bubbles)• production of sound, heat, light• an explosion• formation of a precipitate• disappearance or appearance of a
substance
Phase changes are Physical Changes
• Potential Energy (PE)
energy due to position or condition
at the atomic level refers to the distance between the particles
closer= lower PE farther = higher PE
Potential Energy determines Phase of Matter
• Kinetic Energy (KE)
energy due to motion
Faster=higher KE Slower= lower KE
Kinetic Energy determines Temperature
Energy & Phase Changes
• Adding or removing energy (heat) to a substance can cause it to phase change
• During a phase change, temperature does not change
Heating Curve of Water
Solid
Melting Liqui
d
AB
-heat Δ KE
-move faster
-temp. -solid
BC
-heat Δ PE
-get farther apart
-temp. stay same
-melting
CD
-heat Δ KE
-move faster
-temp. -liquid
Boiling
Gas
DE
-heat Δ PE
-get farther apart
-temp. stay same
-boiling
EF
-heat Δ KE
-move faster
-temp.
-gas
A
BC
DE
F
AB
-KE
-slows down
-temp.
-Gas
BC
-PE
-closer together
-temp. stays same
-Condensation
CD
-KE
-slows down
-temp.
-Liquid
A
BC
DE
F
DE
-PE
-closer together
-temp. stays same
-Freezing
EF
-KE
-slows down
-temp.
-Solid
Boiling
Boiling Point
MeltingMelting Point
FreezingFreezing Point &
What is the boiling point?
What is the melting point?
What is the freezing point?
If melting & freezing points are at the same temperature. . . how do you know which is which?
It depends on whether adding or removing energy!
What is this substance?-Water
How do you know?-Boiling & melting & freezing
points of water
Pre Lab questions
1. Sketch a basic, hypothesized Heating Curve of Lauric Acid.
2. Sketch a basic, hypothesized Cooling Curve of Lauric Acid
3. Sketch a diagram of the set-up for this laboratory.
4. If you spill Lauric Acid on your skin what is the procedure for cleansing it.