Note:

IGCSE Chemistry Revision Notes on Acids Bases and Salts

Syllabus Objectives:

8.1 The characteristic properties of acids and bases

Core 

• Describe the characteristic properties of acids as reactions with metals, bases, carbonates and effect on litmus and methyl orange 
• Describe the characteristic properties of bases as reactions with acids and with ammonium salts and effect on litmus and methyl orange
• Describe neutrality and relative acidity and alkalinity in terms of pH measured using universal indicator paper (whole numbers only) 
• Describe and explain the importance of controlling acidity in soil

Supplement

• Define acids and bases in terms of proton transfer, limited to aqueous solutions 
• Describe the meaning of weak and strong acids and bases

8.2 Types of oxides

Core 

• Classify oxides as either acidic or basic, related to metallic and non-metallic character

Supplement 

• Further classify other oxides as neutral or amphoteric

8.3 Preparation of salts

Core 

• Demonstrate knowledge and understanding of preparation, separation and purification of salts as examples of some of the techniques specified in section 2.2.2 and the reactions specified in section 8.1

Supplement

• 
  
  Demonstrate knowledge and understanding of the preparation of insoluble salts by precipitation 
• Suggest a method of making a given salt from a suitable starting material, given appropriate information

8.4 Identification of ions and gases

Core

• Describe the following tests to identify: aqueous cations: aluminium, ammonium, calcium, chromium(III), copper(II), iron(II), iron(III) and zinc (using aqueous sodium hydroxide and aqueous ammonia as appropriate). (Formulae of complex ions are not required.) cations: use of the flame test to identify lithium, sodium, potassium and copper(II) anions: carbonate (by reaction with dilute acid and then limewater), chloride, bromide and iodide (by reaction under acidic conditions with aqueous silver nitrate), nitrate (by reduction with aluminium), sulfate (by reaction under acidic conditions with aqueous barium ions) and sulfite (by reaction with dilute acids and then aqueous potassium manganate(VII)) gases: ammonia (using damp red litmus paper), carbon dioxide (using limewater), chlorine (using damp litmus paper), hydrogen (using lighted splint), oxygen (using a glowing splint), and sulfur dioxide (using aqueous potassium manganate(VII))