Concepts (A,B,S)

• acid + carbonate -> salt + carbon dioxide + water
• An acid is a substance that produces hydrogen ions (H+) when dissolved in water.
• A strong acid undergoes complete dissociation in water
• A weak acid undergoes partial dissociation in water
• The basicity of an acid is the number of hydrogen ions that can be produced per molecule of acid when dissolved in water.
• strong acids -> HCL, H2SO4, HNO3,
• Weak acids -> H3PO4, H2CO3, CH3COOH
• Water must be present before acids exhibit their acidic properties as it lets acids ionise to form H+ ions
• The strength of an acid is based on its degree of ionisation in water
• Acid + Metal -> Salt + Hydrogen Gas
• Acid + Base/Alkali -> Salt + water
• A base is a metal oxide, hydroxide or aqueous ammonia which reacts with an acid to give salt and water only
• An alkali is a soluble base. When dissolved in water, it produces hydroxide ions (OH-) in solution.
• Neutralisation is the process whereby an acid reacts with a base to form a salt and water only.
• A strong alkali undergoes complete ionisation in water
• A weak alkali undergoes partial ionisation in water
• base + acidic oxide -> salt
• base + ammonium salt -> salt + water + ammonia
• Lime/Quicklime is calcium oxide, CaO(s)
• Slaked lime is calcium hydroxide, Ca(OH)2(s)
• Limewater is calcium hydroxide, Ca(OH)2 (aq)
• Limestone/marble/chalk is calcium carbonate, CaCO3(s)
• The 4 types of oxides are acidic, basic, amphoteric and neutral
• Basic oxides: react with acids to form salt and water; Na2O, MgO, CuO
• Amphoteric oxides: reacts with both acids and alkalis to form salt and water; ZnO, Al2O3, PbO
• Acidic oxides: reacts with bases to form salt and water; SO2, CO2, NO2
• Neutral oxides: has no effect on litmus; NO, CO, H2O
• All Sodium, Potassium and Ammonium salts are soluble
• All nitrate salts are soluble
• All halides (group 17) are soluble except lead and silver.
• All sulfates are soluble except calcium, barium and lead
• All carbonates are insoluble except sodium, potassium and ammonium
• All hydroxides and oxides are insoluble except sodium, potassium and ammonium
• Preparation of soluble salts: Titration and adding excess insoluble solid to a fixed volume of acid
• Preparation of insoluble salts: precipitation
• methyl orange will turn from orange to red in acids and yellow in alkalis
• screened methyl orange will turn from green to grey in acids and green in alkalis