Metals and Non-Metals Notes

Metals and Non-Metals

Learning Objectives & Success Criteria

  • Locate metals and non-metals on the periodic table.
  • Describe the properties of metals and non-metals.
  • Classify an element as a metal or non-metal.
  • Understand the difference between metals and non-metals.

Sorting Elements

  • Elements can be grouped based on properties.
  • Sorting activity: Group elements and explain the sorting criteria based on properties.

Properties of Metals and Non-Metals

  • Examples of elements to consider: sodium, gold, calcium, copper, iron, neon, carbon, sulfur, helium, nitrogen.

Location on the Periodic Table

  • Metals are generally located on the left side of the periodic table; non-metals are on the right.
  • A "stepped line" visually separates metals and non-metals on the periodic table.
  • Hydrogen (H) is a non-metal but is often placed in the middle of the periodic table.

State at Room Temperature

  • Many non-metals have low boiling points, existing as gases at room temperature.
  • Most metals are solids at room temperature, except for mercury (Hg), which is a liquid.
  • Metals generally have high melting points.

Determining Metal vs. Non-Metal

  • If an element is a gas at room temperature, it is a non-metal.
  • If an element is a liquid or solid, it could be either a metal or a non-metal, requiring further investigation.

Properties of Metals and Non-Metals (Detailed)

  • Physical Properties: assessed using a "properties circus" with stations and equipment.
  • Properties Table: Used to record observations when testing elements.
    • Columns: element name, shiny, ductile, malleable, brittle, magnetic, conductor of heat, conductor of electricity, sonorous, high density.
    • Use ticks ($\checkmark$) or crosses ($\times$) to indicate the presence or absence of a property.

Key Questions for Investigation

  • How to determine if an unknown element is a metal or non-metal.
  • Typical properties of metals.
  • Typical properties of non-metals.
  • Are properties consistent across all metals or all non-metals?

Magnetism and Metals

  • Magnetic materials are metallic, but not all metals are magnetic.
  • Only iron (Fe), nickel (Ni), and cobalt (Co) are magnetic.
  • Lack of magnetic attraction does not exclude an element from being a metal.

Chemical Properties - Reaction with Oxygen

  • Elements react with oxygen to form oxides.

  • Metal oxides typically dissolve in water to produce alkaline solutions.

  • Non-metal oxides usually dissolve in water to form acidic solutions.

    • Example reactions:
      • carbon+oxygen→carbon dioxide\text{carbon} + \text{oxygen} \rightarrow \text{carbon dioxide}
      • copper+oxygen→copper oxide\text{copper} + \text{oxygen} \rightarrow \text{copper oxide}

Summary of Properties

  • Metals:
    • Shiny.
    • Good conductors of electricity.
    • Ductile.
    • Malleable.
    • High density.
    • Sonorous.
    • Good conductors of heat.
    • Oxides form alkaline solutions.
  • Non-Metals:
    • Dull.
    • Poor conductors of electricity.
    • Brittle.
    • Low density.
    • Not sonorous.
    • Poor conductors of heat.
    • Oxides form acidic solutions.

Exceptions to General Properties

  • Not all metals exhibit all typical metallic properties, and the same applies to non-metals.
  • Coal (form of carbon) does not conduct electricity, but graphite (another form of carbon) does.
  • Some metals have low densities and can even float.
  • Silicon is a shiny non-metal.

Metalloids

  • Elements with properties of both metals and non-metals.
  • The typical properties of metals and non-metals might lead to think of them as complete opposites.

Identifying Metals, Non-Metals, and Metalloids

  • Based on properties like electrical conductivity, shininess, brittleness, malleability, and ductility.

  • Examples:

    • Germanium: metalloid (conducts electricity at high voltages, shiny, brittle, not malleable or ductile)
    • Lead: metal (conducts electricity, shiny, malleable)
    • Phosphorus: non-metal (does not conduct electricity, not shiny, brittle, not malleable or ductile)

Location of Metalloids on the Periodic Table

  • Metalloids are found around the "stepped line" on the periodic table that separates metals and non-metals.

Examples

  • Cobalt (Co): metal
  • Chlorine: non-metal (green gas)

Determining Whether an Element Is a Metal or Non-Metal Based on Provided Properties

  • If a yellow powder does not conduct heat or electricity and is dull and brittle, it is likely a non-metal.

Summary of Metal Properties

  • Conducts electricity.
  • Shiny.
  • Not brittle.
  • Malleable.
  • Ductile.