IGCC Chemistry Topic: The Periodic Table (Part 2)

Introduction

Examples: Lithium, Sodium, Potassium.
Physical Properties:
- Soft metals, can be cut with a knife.
- Melting points decrease down the group.
- Density increases down the group.
Reactivity with Water:
- Lithium: Reacts slowly, produces fizzing, moves on water surface.
- Sodium: More vigorous reaction, more fizzing, faster movement.
- Potassium: Very vigorous, burns with lilac flame, moves rapidly.
Trend: Reactivity increases as you move down the group.
Predictions:
- Rubidium: Violent reaction with sparks.
- Cesium: Violent explosion.
- Francium: Extremely reactive, difficult to predict.

Examples: Chlorine, Bromine, Iodine.
Molecular Structure: Diatomic non-metals (e.g., Cl₂, Br₂, I₂).
Electron Configuration: 7 electrons in outer shell, forms halide ions with -1 charge.
Physical Properties at Room Temperature:
- Chlorine: Pale yellow-green gas.
- Bromine: Red-brown liquid.
- Iodine: Gray-black solid.
Trend: Density increases and reactivity decreases as you move down the group.
Displacement Reactions:
- More reactive halogen displaces less reactive halogen from compounds.
- Examples:
  - Chlorine displaces Bromine and Iodine.
  - Bromine displaces Iodine.
Reactivity Order: Fluorine > Chlorine > Bromine > Iodine.

Examples: Iron, Nickel, Copper.
Characteristics:
- High densities and melting points.
- Form colored compounds, often act as catalysts.
- Variable oxidation numbers (e.g., Iron: Fe²⁺, Fe³⁺).

Found in Group 8 or Group 0.
Examples: Helium, Neon, Argon.
Properties:
- Unreactive due to stable electron configuration.
- Monoatomic gases.
- No tendency to form bonds due to filled electron shells.
Examples of Stability:
- Helium: 2 electrons in single shell.
- Neon: 2 electrons in first shell, 8 in second shell.

Summary of properties and trends in Groups 1 and 7, transition elements, and noble gases.
Discussions on reactivity and predictions based on periodic trends.