Chemistry Unit Test

SNC 1W1 Chemistry Unit Review - Study Notes

Matter and Change

1. Matter: Anything that has mass and takes up space.

2. Physical vs. Chemical Properties:

   • Physical: No change in composition, just state or form (e.g., color, shape, melting point).

   • Chemical: A substance changes into a different substance (e.g., combustion, rusting).

   • Qualitative: Observed with senses, not measured (e.g., color).

   • Quantitative: Measured with a number (e.g., mass, temperature).

3. Signs of a Chemical Reaction: Gas formed, precipitate formed, color change, odor change, heat/light produced, new substance.

4. Physical vs. Chemical Change:

   • Shredding paper: Physical, no new substance.

   • Toasting marshmallows: Chemical, new substance formed.

   • Cooking an egg: Chemical, new substance formed.

   • Melting a popsicle: Physical, change of state.

5. Example of Properties in Use: Copper bottom on frying pans for heat conduction.

6. Element or Compound?:

   • Water: Compound.

   • Sulfur: Element.

   • Propane: Compound.

Elements and Compounds

7. Subatomic Particles:

   • Proton: Positive, mass 1, in nucleus.

   • Electron: Negative, mass 1/2000, orbiting nucleus.

   • Neutron: Neutral, mass 1, in nucleus.

8. Terms:

   • Mixture vs. Solution: Mixture has multiple parts; solution is uniform.

   • Element vs. Compound: Element has one type of particle; compound has multiple.

   • Heterogeneous vs. Homogeneous: Heterogeneous has different parts visible; homogeneous is uniform.

Models of the Atom

9. Atomic Models:

   • Dalton: Atoms are indivisible.

   • Thomson: Discovered electrons.

   • Rutherford: Atoms have a small, dense nucleus.

   • Chadwick: Discovered neutrons.

   • Bohr: Electrons orbit the nucleus in fixed energy levels.

Element Chart

10. Atomic Information: Use periodic table for atomic number, mass number, protons, electrons, neutrons. Example:

• Oxygen (O): Atomic #8, Mass #16, Protons=8, Electrons=8, Neutrons=8.

• Magnesium Ion (Mg²⁺): Loses 2 electrons, charge +2.

Chemical Formulas and Compounds

11. Vinegar (CH₃COOH): Elements: Hydrogen (4), Carbon (2), Oxygen (2).

12. Types of Compounds:

• Propane (C₃H₈): Molecular compound.

• Potassium iodide (KI): Ionic compound.

• Sulfur (S): Element.

• Oxygen (O₂): Diatomic molecule.

• Water (H₂O): Molecular compound.

Periodic Table

13. Groups on the Periodic Table:

• Noble Gases: Group 18, non-reactive (full outer shell).

• Alkali Metals: Group 1, very reactive (1 valence electron).

• Halogens: Group 17, reactive (7 valence electrons, needs 1 more to be stable).

• Alkaline Earth Metals: Example: Beryllium (Group 2).

14. Element Reactivity:

• Noble Gases: Non-reactive, stable outer shell.

• Alkali Metals: Reactive, easily lose 1 electron.

• Halogens: Reactive, easily gain 1 electron to become stable.

15. Metals, Non-Metals, and Metalloids:

• Metals: Conduct heat/electricity, shiny, malleable.

• Non-metals: Poor conductors, brittle, often gases.

• Metalloids: Have properties of both metals and non-metals.

These notes cover the key concepts for your review. Make sure to practice answering questions from memory to solidify your understanding!