9 Science 1.1-1.3

• An element is a pure substance that cannot be

  broken down into simpler substances through

  physical or chemical methods.
• A compound is a pure substance that is

  composed of two or more elements that are

  chemically combined. A compound can be

  broken down into its elements only by chemical

  methods.
• a mixture is a material made up of two or more different chemical substances which are not chemically bonded
• Mechanical Mixture: a mixture where you can see all components separately (pizza is an example)
• Solution: a mixture where you can not see all components separately (salt water is an example)
• Matter is anything that has mass and occupies

  space.
• List the particle Theory of Matter:

  • All matter is made up of tiny particles.

  • Each pure substance has its own kind of

  particle which is different from the particles of

  other pure substances.

  • Particles attract each other.

  • Particles are always moving.

  • Particles at a higher temperature move faster,

  on average, than particles at a lower

  temperature.
• Element:

  is a pure substance that cannot be

  broken down further by chemical or

  physical methods
• Compound:

  is a pure substance that is made

  of two or more different elements

  that are chemically combined

  salt (sodium chloride), water
• A compound has two or more different elements

  that are chemically compound. While a mixture

  has two or more particles or has more than one

  kind of particles.
• List different ways on how to separate

  mixtures:

  filtering or sifting,

  distillation, evaporation,

  use of magnets, and by hand
• A physical property is a characteristic of a

  substance that can be observed and measured

  without changing the identity of the substance.
• Qualitative physical properties include colour,

  odour, taste, texture, luster and malleability.
• Quantitative physical properties include

  viscosity, melting point, boiling point, solubility,

  hardness, conductivity, and density.
• What are the states of matter?

  Solid, Liquid, Gas and Plasma
• Changes of state of matter

  A) Deposition

  B) Sublimation

  C) Freezing

  D) Melting

  E) Condensation

  F) Boiling

  
• Solid: Holds shape and has a fixed volume
• Liquid: Shape of container, free surface and fixed volume
• Gas: Shape of container and volume of container
• Solubility is the measure of the ability of a a

  substance to dissolve in another substance.

  • The solubility of a substance is expressed as

  a concentration.

  • UNITS - mass of solute/mass of solvent

  or mass of solute/volume of solvent
• What is the reported solubility of sodium

  chloride?

  • NaCl in water at 25 °C at STP is 39.5 g/100 mL.
• What is an aqueous solution?

  • Aqueous solution means solution with water as

  a solvent. (Water is known as the universal

  solvent.)
• A solute is the substance that is being

  dissolved.

  Solvent is the dissolving medium. Examples: salt and water, sugar and water
• The majority of diamonds are used in industry

  to aid in drilling, cutting and grinding.

  Properties – hardness, high lustre,

  transparency, low reactivity with chemicals,

  high thermal conductivity, low electrical

  conductivity, and high density.
• Why do you think people often check to see if

  diamond is real by rubbing it against glass?

  Because a diamond is much harder than glass,

  a diamond will scratch glass. If no scratches

  appear, this may indicate the diamond is not

  genuine.
• Why is copper used as electrical wires?

  Copper is an excellent conductor of electricity.

  This means it can carry an electrical current

  without much energy loss. This makes it ideal

  for electrical wires, since the primary purpose of

  a wire is to provide a pathway for electrical

  energy.
• Unique Properties of Water

  • Solid state that is less dense than its liquid

  state

  • Ability to absorb large amounts of heat

  • Ability to dissolve numerous essential

  chemicals and nutrients
• Water is the only natural substance that exists in 3

  phases.

  Water is the universal solvent because it dissolves

  more substances than any other liquid.

  Water can absorb a lot of heat before it can get hot.

  • Water in its solid form, ice, is less dense than its

  liquid form.
• A chemical property of an element or a

  compound describes its ability to react with

  other substances and form new substances.
• Chemical properties of a substance include

  reactivity with other substances,

  combustibility, stability, and toxicity.
• When is the chemical property of a substance

  exhibited?

  The chemical property of a substance is

  exhibited during a chemical reaction.
• In a point form, summarize the 4 reactivities of

  substances:

  Reactivity with water

  Reactivity with oxygen

  Reactivity with acids

  Reactivity with another substance
• Combustibility is the ability of a substance to

  burn in air.
• How could the combustibility of a substance

  influence how the substance is used?

  to avoid accidents/take extra precautions

  • to take advantage of the large amount of heat

  produced by substances that are

  combustible.
• Define stability and toxicity. Explain how

  stability and toxicity can work together to

  increase the effects of a chemical on the

  environment:

  • Stability is the ability of a substance to remain

  unchanged.

  • Toxicity is the ability of a substance to cause

  harmful effects.

  • The toxic effects of DDT are made worse by

  its stability. If DDT easily broke down, then it

  would not bioaccumulate and biomagnify, and

  its toxic effects on animals and humans would

  be lower.