concept attainment exercise

Diagrams that are examples and non-examples of a specific concept will be shown

Make your own observations and try to notice what concept surrounds the examples

Keep your observations to yourself, we will share them with each other later

Test diagrams will follow to see if you have made the right observations

Examples1) Sand in water2) Quartz crystal3) Cigarette smoke4) Brass trumpet5) Pepper

Non-examples1) Distilled water2) Diamond crystal3) Neon gas in tube4) Silver trumpet5) Salt

What do you think?

What do all the examples have in common?

What do all the non-examples have in common?

All the examples showed pictures of mixtures sand in water, quartz crystal, cigarette

smoke, brass trumpet, pepper, milk, oil in water, salt water, honey

All the non-examples were pictures of pure substances distilled water, diamond, neon gas, silver

trumpet, salt, pencil lead

Matter Flowchart

MATTER

Can it be physically separated?

Homogeneous Mixture

(solution)

Heterogeneous Mixture Compound Element

MIXTURE PURE SUBSTANCE

yes no

Can it be chemically decomposed?

noyesIs the composition uniform?

noyes

Colloids Suspensions

A pure substance contains only one kind of molecule.

That molecule can be either an element or a compound.

Ex. Water is a compound of H-O-H. Ex. A diamond is an element molecule of

C-C-C (n) It can’t be separated by physical means

Element Compound

Elements are composed of identical atoms

EX: copper wire, aluminum foil

Compounds are made of two or more different elements in a fixed proportion

EX: Salt (NaCl)

A) A clear, colourless liquid that can be chemically split into two gases – each with different properties

B) A yellow solid that always has the same properties and cannot be broken down chemically

C) A colourless gas that burns in oxygen to produce carbon dioxide and water

Mixtures

Variable combination of 2 or more pure substances (or other mixtures).

Heterogeneous Homogeneous

A homogeneous mixture is a mixture with only one visible phase (dissolved substance in solvent)

Original state of solute Solvent Examples

Gas Gas Air, natural gas

Gas Liquid Carbonated drinks, water in rivers containing oxygen

Gas Solid Hydrogen in platinum

Liquid Gas Water vapour in air, gasoline-air mixture

Liquid Liquid Alcohol in water, antifreeze

Liquid Solid Amalgams, such as mercury in silver

Solid Gas Mothballs in air

Solid Liquid Sugar or salt in water

Solid Solid Alloys, copper-nickel in coins

Mixtures: Heterogeneous

Solutions homogeneous small-sized particles No Tyndall effect (do not scatter light) particles don’t settle EX: tea

Mixtures: Homogeneous

Some metals that we use every day exist because they are mixtures.

Bronze = tin + copper

Brass = copper + zinc

These metal mixtures are called ALLOYS

Mixtures: Heterogeneous

Colloids homogeneous medium-sized particles Tyndall effect (do scatter light) particles don’t settle EX: milk

A heterogeneous mixture is a mixture with two or more visible phases

Mixtures: HeterogeneousSuspension

heterogeneous large particles Tyndall effect (do scatter light) particles settle EX: fresh-squeezed

lemonade

Mixtures & the Tyndall Effect- scattering of light by particles - a way to tell the difference

between solutions and colloids and suspensions

Mixtures & the Tyndall Effect

Laser light passes through Laser light passes through Laser light does NOT pass No scattering with scattering through – most/all light is

scattered

Mixtures & the Tyndall Effect

More Terms…

Each Element is made of one kind of atom.

An atom is the smallest indivisible particle of matter

A molecule is a combination of two or more atoms

Oxygen HydrogenWater