Unit B grade 9

Chemistry

The process of studying properties of matter and how matter changes.

Matter

Anything that has mass and takes up space.

What does the yellow triangle mean?

Caution.

What does the orange diamond mean?

Warning.

What does the red octagon mean?

Danger.

WHMIS

Workplace Hazardous Materials Information System

What are the three states of matter?

Solid, gas, liquid.

What is it called when a solid changes to a liquid?

Melting.

What is it called when a liquid changes to a gas?

Evaporation.

What is it called when a gas changes to a liquid?

Condensation.

What is it called when a liquid changes into a solid?

Freezing.

What is it called when a solid changes into a gas?

Sublimation.

What is it called when a gas changes into a solid?

Deposition.

Properties

Characteristics that are used to describe a substance.

What are the two properties of matter?

Physical and chemical.

What are physical properties?

When matter undergoes physical changes in its appearance or state of matter but its composition remains the same. ex. ice cream melted is still ice cream.

What are chemical properties?

How a substance interacts with another substance. It includes substances reacting with acid, the substances ability to burn, reaction to water, etc. When a chemical change occurs, a different substance of several substances are formed. Ex. The bateer of a pancake mixed vs the cooked pancake.

Pure substance

Only made up of one kind of matter and have a unique set of properties that set it apart from any other kind of matter. It can be an element or a compound. Ex. mercury or sugar.

Element

A material that cannot be broken down into any simpler substances. They are building blocks for compounds. Elements are located on the periodic table.

Compound

When 2 or more elements combine chemically in fixed proportion. ex. h20 - 2 hydrogens and 2 oxygens.

Heterogenous mixture

Combinations of pure substances. Substances in a mixture do not combine chemically - they remain in their original form. You can see the different substances that make up the mixture. Ex. trail mix.

Solution/homogenous mixture

You cannot see the different substances that make up the mixture. One substance dissolved is in another. Ex. Sugar in coffee.

Aqueous solutions

Substances are dissolved in water.

Suspension

A cloudy mixture where tiny particles of one substance are held within another. You can filter these particles out through filter paper. Ex. Orange juice with pulp.

Colloid

Cloudy mixture where the tiny suspended particles are so small that they cannot be separated out from the other substances. Ex. Milk.

Give two examples to illustrate the difference between a physical and chemical property.

Physical property: When matter undergoes physical change like the different items in a trail mix you can physically see, Chemical property: How a substance interacts with another substance like how under a microscope you can see the different particles of the flour, egg, etc. When the pancake is cooked, they all mold together and you cannot see separate particles.

What is the difference between a pure substance and a mixture?

Pure substances: Only made of one kind of matter, Mixture: Combinations of pure substances.

Classify the following substances as an element, compound, or mixture: Pop is composed of water, sugar, and carbon dioxide. Graphite in a pencil is composed of carbon. Carbon dioxide is composed of carbon and oxygen.

Pop: mixture, Graphite: element, Carbon dioxide: compound.

When did the first chemists live and during what Age?

Before 8000 B.C. during the Stone Age and fire changes their lives.

When did early chemists investigate materials that held high value like gold and copper?

Between 6000-1000 B.C.

What is bronze, and when did chemists discover it?

Bronze is produced when copper and tin are heated together, and they discovered it in 4500 B.C.

When did Hittites discover how to extract it from rocks?

1200 B.C.

How did the Hittites in 1200 B.C. use iron to produce steel?

The combined iron with carbon to produce steel which was sharper.

When and who stated that each type of material was made up of a different type of atomic?

In 400 B.C. Democritus stated that all matter is composed of indivisible particles called atoms, differing in size and shape.

When and who stated that everything was made up f earth, fire, and water? How long was this idea accepted for?

in 350 B.C. Aristotle stated this idea. His idea was accepted for 2000 years.

What did Alchemists do?

He preformed the first chemical experiments and invented beakers and filters.

What did Robert Boyle do?

He experimented with the behavior of gases and found out that Democritus ideas were actually more correct than Atistole.

What did Antonine Lavoisier do?

He studied the chemical interactions and developed a system of naming chemicals. He is called the father of modern chemistry.

What did John Dalton do and when?

He suggested that matter is made up of elements in 1808. His theory stated that all atoms in an element are identical in mass and no two elements have atoms of the same mass. He used a model called the “billiard ball model" which are tiny atoms like speres.