Chemistry SNC1D1 Grade 9 Science

Matter Matter is anything that has mass and takes up space

Particle Theory of Matter 1. All matter is made up of tiny particles that have empty spaces between them 2. Different substances are made up of different kinds of particles 3. Particles are in constant random motion 4. Particles of a substance move faster as its temperature increases 5. Particles attract each other

States of Matter SolidLiquidGas

Solids Have a fixed volume Atoms can only vibrate in place E.g. gold, paperclip, ice Atoms are packed very close together, and forces of attraction are strong. They can’t move much

Liquids Allows liquids to flow and slosh around Fixed volume, but no fixed shape E.g. oil, glue, water Atoms can slide by each other because attraction is weaker and can no longer hold them together

Gases Gases of no fixed volume or shape They fill any container they are put inside E.g. air, helium, water vapour (steam) Atoms have lots of energy: they fly past each other and are far apart.

Changes of State states-of-water states-of-water

Changes of State Increasing the temperature increases the energy of particles so that matter can change state.

Changes of State - summary

Still the Same! When a substance changes state, the type of atom DOES NOT CHANGE!

This is called a Physical Change Other examples: Change of state: melting chocolate Dissolving: sugar in water Change of shape: melting candle wax, ripping paper, kneading play-do *Most physical changes are easy to reverse.

Chemical Changes Always involve the production of new substances Most chemical changes are hard to reverse E.g. burning toast, cooking (an egg), rusting of a nail, bleaching a stain, tarnishing of silver

Evidence of chemical change:

Classification of Matter

Pure Substances E.g. pure or distilled water only contains water particles (note: tap water is not a pure substance because it contains other types of particles, such as dissolved gases) A substance that is made up of only one type of particle

Mixtures HETEROGENEOUS (Mechanical mixtures) means “different” HOMOGENEOUS (Solutions) means “the same” A substance that is made up of at least two different types of particles 2 types: You can see the different parts of the mixture easily You cannot see the different parts of the mixture easily

Mechanical Mixtures

Homogenous Mixtures or Solutions

Solute vs. solvent Solute: substance that dissolves in the solvent (ex. sugar) Solvent: the solution used to dissolve the solute. (ex. water)

Liquids or gas mixtures are “solutions” if they are CLEAR! If they appear murky or opaque, it is a mechanical mixture.

Review: Pure substance, mechanical mixture, or solution? Sugar

Review: Pure substance, mechanical mixture, or solution? Perfume

Review: Pure substance, mechanical mixture, or solution? Chocolate fudge sundae

Review: Pure substance, mechanical mixture, or solution? Cranberry juice

Review: Pure substance, mechanical mixture, or solution? Gold

Review: Pure substance, mechanical mixture, or solution? Hand soap with antibacterial beads

Review: Pure substance, mechanical mixture, or solution? Soil