UNIT III Lesson 1Physical Properties &

Physical Changes of Substances

HEBDEN TEXTBOOK

Read page 41 and 42 carefully. Focus on all the definitions listed in it and the

additional comments sections. Write out notes for yourself to remind you of

important info that you read ( like a mini summary)

You have 15 mins.

Go, go, go…allez allez allez!

III.1 BASIC DEFINITIONS

Describing substances Qualitative information is ___________________

information Quantitative information is __________________

information

BASIC DEFINITIONS

An observation:

An interpretation (inference):

A description:

Data (quantitative) usually from experiments.

An experiment:

*page41

III.1 BASIC DEFINITIONS

What is the difference between a HYPOTHESIS and a THEORY?

HYPOTHESIS vs THEORY/Model

III.1 BASIC DEFINITIONS

LAW: Broad ____________ or summary statement that describe a ______________________________ to explain how nature behaves when a particular situation occurs.

They do not__________________________________________

They are not_________________________________________

WHAT IS CHEMISTRY ANYWAY ?!

Chemistry is ...The study of the properties, composition and behaviour of matter…MATTER is anything that has _____________ and occupies a ______________

PROPERTIES, COMPOSITION AND MATTER

Property is a characteristic, a trait or quality that something has

Ex: water boils at 100 °C

Composition is what something is made up of…its basic nature from the inside (its ingredients)

EX: water is made up of two hydrogen atoms and 1 oxygen atom H20.

III.2 THE PHYSICAL PROPERTIES OF MATTER

Substance is something unique with a set of unique properties.

Properties of matter

PHYSICAL vs CHEMICAL

PROPERTY PROPERTY/Rxns

It is a property that is found

without creating a new substance.

Ex: colour, density, hardness, melting point, boiling point, pH, viscosity, etc…

It is when a new substance is created due to undergoing chemical reactions.

Ex: hydrogen can burn in air (Oxygen) and produce waterHydrogen reacts with chlorine to produce hydrogen chloride.

III.2 THE PHYSICAL PROPERTIES OF MATTER

Physical properties can be Extensive or Intensive:

EXTENSIVE vs. INTENSIVE

Depends on the amount of substance present (extent). •Ex: Mass, volume, shape, height…• they depend on the amount you have.

Depends only on the nature of the substance, not on how much you have of it.•Ex: density, m.p. color•Used to identify substances since they do not change.

III.2 THE PHYSICAL PROPERTIES OF MATTER

STATES OF MATTER Matter can exist in three common states or

phases:_______, _______, and _______.

http://www.chem.purdue.edu/gchelp/liquids/character.html

III.2 THE PHYSICAL PROPERTIES OF MATTER

Phase Shape Volume Change when heated

Space between particles

SOLID

LIQUID

GAS

ARE THERE OTHER STATES OF MATTER THAT EXIST ?!

FOR YOUR INFORMATION ONLY

III.2 THE PHYSICAL PROPERTIES OF MATTERMore physical properties to know (page 46)Hardness: resistance of abrasion or scratching.

III.2 THE PHYSICAL PROPERTIES OF MATTER

More physical properties/definitions to know (page 46). Diffusion: intermingling of fluids (liquids and gases)

VAPOR VS GAS

Gases are in a gaseous state at room temperature. The molecules in a gas can expand to occupy any available volume. On the other hand, the molecules of a vapor gain energy and vaporize from a substance which is either a solid or liquid at room temperature

Vapour: it is a gas caused by the evaporation of a substance which naturally boils above room temperature (20-23.5 C )

Vapour Pressure: pressure caused by the vapour evaporating from a liquid.

Ex: Acetone or nail polish remover boils at 56 C. So any acetone that evaporates at room temperature

is called a “vapour” and not a “gas”.

AND SOME MORE… Boiling temperature/boiling point:

Temperature at which a liquid turns into ________ .

Freezing point: Temperature at which a ______ turns into a ____________

Melting point is the temperature at which a ____________ turns into a _______________

MALLEABILITY

The ability to be rolled or hammered into thin sheets

DUCTILITY

The ability to be stretched or drawn into wires

VISCOSITY

Resistance to FLOW ! Doesn’t wanna move! More viscous = more lazy

LUSTRE How light is reflected off of a surface (oily, silky, glossy, shiny, etc )

PRACTICE QUESTIONS

QUESTIONS: p. 43 #1-3, 7, 9, 11

QUESTIONS: p. 44 #13 and #15

QUESTIONS: p. 48 #21, 22, 24, 25, 26, 31.

*These are the types of questions to expect on a test for Unit III ( sections 1 and 2)