What is Matter?

Chapter 2 Section 1

Matter

• matter – anything that has mass & takes up space (volume)

Mass vs. WeightMass

• mass - amount of matter an object contains– SI unit is the kilogram (kg)– can be measured using a

balance (triple beam)– mass is the same on Earth

and in space

Weight• weight - a measure of

the force of gravity on an object– SI unit is the Newton (N)– can be measured using a

scale (spring)– depends on gravity, thus is

different on Earth and in space

Physical Properties

Chapter 2 Section 2

Physical Properties• physical property - any

characteristic that can be observed without changing the identity of the matter

Examples:colorshapeodor/smelltastemassvolumestate of matterdensitythermal conductivitymalleabilityductilitysolubility

Color The ability to distinguish Apple is red

Odor The ability to distinguish based on smell

Sulfur has a rotten smell

Mass The amount of matter that something is made of

Is it heavy?

Volume Amount of space taken up Can all the book fit in the backpack?

Thermal Conductivity

The ability to transfer thermal energy from one area to another

Plasticfoam is a poor conductor, so hot chocolate in a plasticfoam cup will not burn your hand

StateThe physical form in which a

substance exists, such as solid liquid, or gas

Ice is water in its solid state

MalleabilityThe ability to be pounded into

thin sheetsAluminum can be rolled or

pounded into sheets to make foil

Ductility The ability to be drawn or pulled into a wire

Copper is often used to make wirings

Solubility The ability to dissolve in another substance

Sugar dissolves in water

DensityMass per unit volume Lead is used to make sinkers

for fishing like because lead is more dense than water.

Density

• density – the amount of matter within a given volume

– Demonstration: People in a square

Which square is more dense?

Density

Now which one is more dense?

Density in Liquid

• Object is MORE dense (higher density) it will SINK

• Object is LESS dense (lower density) it will FLOAT

Liquid Layers• If you pour together

liquids that don’t mix and have different densities, they will form liquid layers.

• The liquid with the highest density will be on the bottom.

• The liquid with the lowest density will be on the top.

Liquid Layers• Which layer has the highest density?• Which layer has the lowest density?• Imagine that the liquids have the

following densities: – 10g/cm3

– 3g/cm3

– 6g/cm3

– 5g/cm3

Which number would go with which layer?

Density

•

ALWAYS REMEMBER

UNITS!

Physical Change

• physical change - a change that changes the appearance of matter but the identity of matter stays the same

• Examples:– cutting– breaking– tearing– melting