7.3.2

Preparing Soluble Salts

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Preparing Soluble Salts

Soluble salts are prepared by reacting acids with alkalis, metals, bases, or carbonates. Steps involve reaction, filtration, evaporation for crystals, and drying.

Illustrative background for Introduction to soluble salts preparationIllustrative background for Introduction to soluble salts preparation ?? "content

Introduction to soluble salts preparation

  • Soluble salts dissolve well in water.
  • Chemists prepare soluble salts by reacting acids with other substances.
    • The four main methods: titration with alkali, excess metal, excess insoluble base, and excess insoluble carbonate.
    • Each method requires separation and purification steps.
Illustrative background for Preparation by titration with alkaliIllustrative background for Preparation by titration with alkali ?? "content

Preparation by titration with alkali

  • Use an acid and an alkali to make soluble salts by titration.
  • Slowly add alkali to acid until neutralisation occurs (pH 7).
  • Record the exact volumes when neutral.
  • Repeat without indicator, then evaporate water to crystallise salt.
  • Separate crystals by filtration and dry them.
Illustrative background for Preparation using excess metal, base or carbonateIllustrative background for Preparation using excess metal, base or carbonate ?? "content

Preparation using excess metal, base or carbonate

  • React acid with excess metal (like zinc), base (like copper oxide), or carbonate (like calcium carbonate).
  • The acid reacts until all the acid is used up.
  • Filter to remove leftover solids.
  • Evaporate the filtrate to crystallise pure soluble salt.
Illustrative background for Separation and purification of saltsIllustrative background for Separation and purification of salts ?? "content

Separation and purification of salts

  • After reaction, solutions must be filtered to remove solids.
  • Evaporate the solution gently to form crystals.
  • Crystals form as the solution concentrates.
  • Dry crystals with filter paper to purify.
    • This process yields pure soluble salts for experiments.
Illustrative background for Hydrated and anhydrous substancesIllustrative background for Hydrated and anhydrous substances ?? "content

Hydrated and anhydrous substances

  • Hydrated substances contain water molecules chemically joined.
  • Anhydrous substances have no water.
    • Example: Copper sulfate turns blue when hydrated, white when anhydrous.
  • Water of crystallisation affects the appearance and properties.

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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