3.4.2 Extracting Metals Low in the Activity Series

Description

Quick Overview

This section focuses on the extraction of metals that are low in the activity series, detailing the methods, such as heating, that facilitate their extraction from ores.

Standard

Metals low in the activity series are characterized by their unreactiveness, making it possible to extract them from their ores by simple heating. The section discusses specific examples, such as mercury and copper, and highlights the chemical processes involved in their extraction.

Detailed

Extracting Metals Low in the Activity Series

Metals that rank lower in the activity series are known for their low reactivity. This characteristic allows for their extraction from ores primarily through heating rather than more complex chemical processes. An example includes mercury, which is extracted from its ore, cinnabar (HgS). During extraction, cinnabar is first heated in the presence of air to produce mercuric oxide (HgO), which upon further heating breaks down to yield liquid mercury and oxygen gas. The reactions can be represented as:

  1. Heating Cinnabar:
    2HgS(s) + 3O₂(g) → 2HgO(s) + 2SO₂(g)
    This step converts the ore to a more reactive oxide.
  2. Reducing Mercuric Oxide:
    2HgO(s) → 2Hg(l) + O₂(g)
    The mercuric oxide is reduced to produce elemental mercury.

Additionally, copper can be extracted from its ore, chalcopyrite (Cu₂S), by similarly heating it in air to produce copper(I) oxide and sulfur dioxide before further heating leads to the generation of elemental copper:

  1. Heating Chalcopyrite:
    2Cu₂S + 3O₂(g) → 2Cu₂O(s) + 2SO₂(g)
  2. Reducing Copper(I) Oxide:
    2Cu₂O + Cu₂S → 6Cu + SO₂(g)

The significance of this section lies in understanding the direct processes involved in metal extraction, emphasizing the chemical reactions that reduce metal oxides to their elemental forms, which is crucial for metallurgy.

Key Concepts

  • Low Reactivity: Metals low in the activity series can be extracted through heating.

  • Mercury Extraction: Cinnabar is heated to obtain mercuric oxide.

Memory Aids

🎵 Rhymes Time

  • To get mercury, treat cinnabar with heat, reducing it down to liquid neat.

📖 Fascinating Stories

  • Once in ancient mines, cinnabar was found; with heat applied, mercury would abound.

🧠 Other Memory Gems

  • Remember 'CCM' for Cinnabar Conversion to Mercury.

🎯 Super Acronyms

COP

  • Cinnabar
  • Ore
  • Process for deriving mercury.

Examples

  • Mercury is extracted by heating cinnabar, leading to its reduction from mercuric oxide.

  • Copper is obtained from chalcopyrite by heating, followed by further reactions that yield solid copper.

Glossary of Terms

  • Term: Cinnabar

    Definition:

    An ore from which mercury is extracted.

  • Term: Chalcopyrite

    Definition:

    An ore that contains copper.

  • Term: Reduction

    Definition:

    The process of gaining electrons or decreasing oxidation state.

  • Term: Oxide

    Definition:

    A chemical compound that contains at least one oxygen atom.

  • Term: Thermal decomposition

    Definition:

    A type of chemical reaction involving the breaking down of compounds due to heat.