BELL WORK

Use the Particle Theory to briefly explain the following:

1. Solids have a hard rigid shape and a definite volume.

2. A solid substance expands when heated.

3. A puddle of water disappears on a hot summer day.

4. Gases take the shape and size of their container.

5. A balloon filled with helium gas shrinks when taken outside on a cold winter day.

6. Predict what will happen to the balloon (in #5) if it is brought back inside a warm building.

PHYSICAL PROPERTIES OF MATTER …

LEARNING GOALS

I will be able to describe physical and chemical properties of matter.

I will be able to perform density calculations.

WHAT ARE PHYSICAL PROPERTIES?

Used to describe a substance (doesn’t change what it is)

Can be quantitative (with numbers) or qualitative (no numbers)

Physical change – usually a change of state; can be reversed (no change to the particles)

QUALITATIVE PP

Luster – shiny/dull

Optical clarity – ability to allow light through

Brittleness – breakability or flexibility

Viscosity – ability or a substance to flow

Hardness – ability to scratch

Malleability – ability to be hammered

Ductility – ability to be pulled into a wire

Electrical conductivity – ability to conduct electricity

QUANTITATIVE: FREEZING, MELTING, BOILING POINTS

Involved changes of state (i.e. evaporation, condensation)

Can be looked up in tables (they are constants)

QUANTITATIVE PP - DENSITY

Measure of how much mass is contained within a given volume

Units are usually g/mL (for liquids) or g/cm3 (for solids)

Equation triangle to calculate:

EXAMPLE 1

Calculate the density of a substance that has a mass of 4.5g and a volume of 13.5mL.

EXAMPLE 2

Given the density of aluminum is 2.70 g/cm3, what volume would 200g have?

EXAMPLE 3

The density of ethanol is 0.789 g/mL. What is the mass of a sample with a volume of 125 mL?

CHEMICAL PROPERTIES

Properties that describe how a substance reacts in the presence of another.

A description of a substance that is determined when the composition of the substance is changed.

Chemical property examples include:

Ability to react with water.

Ability to react with acid.

Ability to react with air.

Ability to burn (combustibility).

LEARNING GOAL REVISIT

I will be able to describe physical properties and chemical properties of matter.

I will be able to perform density calculations.

TO DO …

P 182 #2,4,5

P 198 #1

Density Worksheet

Don’t forget that to calculate the volume of a cube, the formula is …