12.5.2

Testing Aqueous Cations 2

Test yourself

Metal Hydroxides

Here are some more examples of the formation of precipitates:

Illustrative background for Copper(II) hydroxideIllustrative background for Copper(II) hydroxide ?? "content

Copper(II) hydroxide

  • Copper ions (Cu2+) form the blue precipitate copper(II) hydroxide.
    • Cu2+(aq) + 2OH-(aq) → Cu(OH)2(s).
Illustrative background for Iron(II) hydroxideIllustrative background for Iron(II) hydroxide ?? "content

Iron(II) hydroxide

  • Iron(II) ions (Fe2+) form the green precipitate iron(II) hydroxide.
    • Fe2+(aq) + 2OH-(aq) → Fe(OH)2(s).
Illustrative background for Iron(III) hydroxideIllustrative background for Iron(III) hydroxide ?? "content

Iron(III) hydroxide

  • Iron(III) ions (Fe3+) form the brown precipitate iron(III) hydroxide.
    • Fe3+(aq) + 3OH-(aq) → Fe(OH)3(s).
Illustrative background for Ammonium ionIllustrative background for Ammonium ion ?? "content

Ammonium ion

  • Ammonium (NH4+) ions form water and ammonia. Ammonia gas evolves out of the solutions.
    • NH4+(aq) + OH-(aq) → NH3(g) + H2O(l).
Illustrative background for Chromium(iii) hydroxideIllustrative background for Chromium(iii) hydroxide ?? "content

Chromium(iii) hydroxide

  • Chromium(III) ions (Cr3+) form a green precipitate.
    • The green precipitate dissolves in excess NaOH.

Jump to other topics

1States of Matter

2Atoms, Elements & Compounds

3Stoichometry

4Electrochemistry

5Chemical Energetics

6Chemical Reactions

7Acids, Bases & Salts

8The Periodic Table

9Metals

10Chemistry of the Environment

11Organic Chemistry

11.1Formulae, Functional Groups & Terminology

11.2Naming Organic Compounds

11.3Fuels

11.4Alkanes

11.5Alkenes

11.6Alcohols

11.7Carboxylic Acids

11.8Polymers

12Experimental Techniques & Chemical Analysis

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