Topic 1 - Stoichiometric Relationships

List the characteristics of matter.

• Made up of particles: atoms, molecules, ions

• The particles are in constant motion

• Occupies volume in space

• Has a mass

What is temperature? As temperature increases, so does what?

Temperature is the average kinetic energy and therefore the KE avg increases with temperature.

Does temperature change when transitioning between states, e.g., melting, boiling, freezing, etc.?

No.

Define a mixture. List two examples.

A mixture is a combination of two or more pure substances that retain their individual properties and are not chemically bonded together.

• Air (many gases)

• Seawater (salt and water)

Define a pure susbstance. List two.

A definite and constant composition.

• Elements

• Compounds

List the two types of mixtures and give define them.

• Homogenous: uniform composition and properties (e.g., saltwater, air) AKA solutions

• Heterogeneous: non-uniform composition and varying properties (e.g., sand, or oil and water) AKA suspensions

Atom of different elements combine to form different compounds in … ?

* Fixed ratios, to give full outer shell of electrons

How can we distinguish between homogenous and heterogenous mixtures?

Its possible to separate heterogenous mixtures, but not homogeneous.

List a few separation techniques.

• Fractional distillation (use boiling points)

• Solition and filtration (use solubility)

• Paper chromatography (absorption)

• Magnet (magnetism)

List two properties of ions.

• Completely dissociate in aqueous solution

• Ions have a positive or negative charge (more or less electrons from their parent atom)

  • Called cations or anions

What is an ionic equation?

An equation that only shows the ions or particles participating in the reaction, they do not include the spectator ions.

What is relative atomic mass?

Weighted average of the isotopes of the atoms of an elemetn relative to carbon-12. OR, the mass of an atomic relative to C-12.