05 Chemical Bonds
06 Acids, Bases and Salts
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6.9.3 Preparing Soluble Salts

Preparing Salts of Potassium, Sodium and Ammonium

  1. Potassium, sodium and ammonium salts are usually prepared through the reactions of acids with alkalis.
  2. Reaction acid with alkali will produce salt and water.
    Acid + Alkali → Salt + Water
  3. The salt is prepared by titration method of acid and alkali using an indicator.

Steps to Prepare the Salts of Potassium, Sodium and Ammonium through Titration

Step 1 – Titration to Find the End Point

  1. The end point is the point in a titration at which the 2 reactants have completely reacted.
  2. An endpoint is often marked by a color change.

Step 2 – Titrate Without Indicator

  1. The product obtain in step 1 is contaminate by the indicator.
  2. The reaction is repeated by using the same amount of reactants as in step 1, without using any indicator.
Step 3 – Crystalisation

Step 4 – Filtration and Drying


Preparing Salts of Non-"Potassium, Sodium and Ammonium"

  1. The salt non-potassium, sodium and ammonium is prepared by reacting acid with insoluble metal/metal oxide/metal carbonate:
    1. Acid + Metal Salt + Hydrogen (Displacement reaction)
    2. Acid + Metal oxide Salt + Water (Neutralisation Reaction)
    3. Acid + Metal carbonate Salt + Water + Carbon Dioxide
  2. Below is the steps in preparing the soluble non-potassium, sodium and ammonium salts.

Step 1 – The Reaction

Add metal/metal oxide/metal carbonate powder until excess into a fixed volume of the heated acid

Step 2 – Filtration 1 to Remove Excess Reactant

Filter the mixture to remove excess metal/metal oxide/metal carbonate

Step 3 – Crystalisation
  1. Evaporate the filtrate until it becomes a saturated solution
  2. Dip in a glass rod, if crystals are formed, the solution is saturated.

Step 4 – Filtration 2 to Collect the Solid Salt

  1. Cooled at room temperature
  2. Filter and dry the salt crystals by pressing them between filter papers.