chapter 3 properties of matter. section 1: what is matter?
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Chapter 3
Properties of Matter
Section 1: What is matter?
Vocabulary
• Matter• Volume• Meniscus• Mass• Weight
Vocabulary
• Matter – Anything that has mass and takes up space
• Volume– Amount of space an object takes up
• Meniscus– Curve at a liquid’s surface
Vocabulary
• Mass– Amount of matter in an object
• Weight– Measure of the gravitational force on an
object
Matter and Volume
• All matter takes up space (volume)• No two objects can occupy the same
space at the same time
Matter and Volume
• Liter (L) is the SI unit for volume• Small liquids are measured in
milliliters (mL)– 1 L = 1,000 mL
• All liquid is measure in L or mL
Matter and Volume
• Measuring liquid– Use a graduated cylinder– Accuracy matters!
Matter and Volume
• Read volume at the meniscus
Get Eye Level
Matter and Volume
• Solid objects measured in cubic units– Cubic = having 3 dimensions
• Cubic meters -- m³• Cubic centimeters -- cm³• Volume = (length) (width) (height)
Matter and Volume
• Irregular shaped objects– Use water displacement to find volume
Matter and Volume
• Water displacement1. Measure starting water amount2. Place object inside graduated cylinder3. Re-measure water amount4. Take difference
Matter and Volume
• Solid objects ALWAYS measured in cubic units– cm³
• Water displacement measures mL• Remember….. – 1 mL = 1 cm³
• So…. Convert mL reading to cm³
Matter and Mass
• Mass never changes based on location– Only if amount of matter changes• Ex: You lose weight• Ex: you cut a piece of wood in ½
• Weight is amount of gravitational force– Changes based upon object’s location in
the universe
Matter and Mass
• Mass measured in grams (g) or kilograms (kg)– 1 kg = 1,000 grams
• Weight measured in newton (N)
Weight measured by spring scale
Mass measured by balance scale
Matter and Mass
Section 2: Physical Properties
Vocabulary
• Physical property• Density• Physical change
Vocabulary
• Physical property– Characteristic of a substance that does not
involve a chemical change• Density – Amount of matter in a given volume
• Physical change– A change of matter from one form to another
form without a change in chemical properties
Identifying Physical Properties
• Physical properties can be observed or measured without changing its identity– Looking at ball’s color– Measuring the ball’s volume
Identifying Physical Properties
• Examples…–Color– Size– Texture / feel–Magnetism– Flexibility– Smell
Identifying Physical Properties• More examples–Ductility• Ability to be pulled into wires–metal
–Malleability• Ability to be pounded into shapes–Metal – think aluminum into various
shapes/containers
• State– Solid, liquid, gas
• Solubility– Ability to dissolve
• Thermal conductivity– Rate which a substances transfers heat
Identifying Physical Properties
Identifying Physical Properties
• Density– Must have a unit of measurement!• g / cm³ -- for solids• g / mL -- for liquids
– Density is constant• If you double the volume of an object,
then it’s mass always doubled
Identifying Physical Properties
Identifying Physical Properties
• Density and Floating / Sinking– Water density = 1 g / mL– If object density greater than 1 g / mL, then
it will sink– If object density less than 1 g / mL, then it
will float
• Find the Density– Object with mass of 42 g and volume of
12 cm³
Identifying Physical Properties
Physical Change: NO NEW Substance
• A change that affects a physical property is a physical change– Twisting a paper clip– Sanding a piece of wood
Physical Change: No new substance
• Most physical changes are reversible• Classic example– Water ice– Ice water– Water steam– Steam water
• Physical changes do not change the identity of the substance
Section 3: Chemical Properties
Vocabulary
• Chemical property– Describes a substance’s ability to participate in
chemical reactions• Chemical change– Occurs when one or more substances change
into an entirely new substance
Identifying Chemical Properties
• Chemical properties describe matters ability to change into a NEW substance
• Examples:– Reactivity• Ability to change into a new substance
– Flammability• Ability to burn
Identifying Chemical Properties
• Physical or chemical property?– physical = something to be observed• Touch, feel, look, weight, smell, etc
– Chemical = composition of matter • Harder to see
Identifying Chemical Properties
• Physical or Chemical?
Identifying Chemical Properties
• Physical or Chemical?
Chemical Changes & New Substance
• Chemical change is the process• Chemical properties describe what
chemical changes will take place
Chemical Changes & New Substance
• Signs of a chemical change– Change of color– Change of odor– Fizz or foam– Light being given off
Chemical Changes & New Substance
• Chemical changes almost always involve heat– Losing heat – exothermic– Gaining heat -- endothermic
Physical vs Chemical Changes
• Physical changes do not changes the substances composition– Ice water steam• It’s all H₂O
• Chemical changes do change the composition because it’s a new substance
Physical vs Chemical Changes
• Most physical changes are easily undone
• Chemical changes are almost impossible to reverse– Think a firework explosion
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