Classify common substances as acidic, basic or neutral * An acid is a substance which in solution produces hydrogen ions, H+ or more strictly H3O+, sometimes called hydronium ions * A base is a substance which either contains the oxide O2- or hydroxide ion OH- or which in solution produces the hydroxide ion. * A soluble base is called an alkali
Common properties of all acids: * Sour taste * String or burn the skin * In solution, acids conduct electricity * Turns blue litmus red
Common properties of alkalis * Have a soapy feel * Bitter taste * In solution, good conductors of electricity * Turns red litmus blue Acid | Base | Neutral | - HCl-lining of stomach, cleaning metals, cleaning bricks, neutralising bases, pH maintenance in swimming pools- Acetic acid (CH3COOH) (systematic name ethanoic acid). Vinegar, made from oxidation of ethanol in wine. Used to flavour and preserve food- Citric acid (C6H8O7) – citrus fruit. Used as a food additive (for flavour and as a preservative)- Carbonic acid (H2CO3) – dissolved in acid rain, in soft drinks. - Sulfuric acid (H2SO4) – used to make fertilisers, synthetic fibres, industrial ethanol, detergents and car batteries-Nitric acid (HNO3) – synthesised in huge quantities for the manufacture of fertilisers and explosives. | -Ammonia (NH3)- stale urine of humans and animals. Sharp penetrating odour. Also formed by anaerobic decay of organic matter (w/out oxygen). It is manufactured in huge quantities for the production of fertilisers, nitric acid. Used in home as cleaning agent.-Metallic oxides – e.g. Iron(III) oxide, copper oxide and titanium oxide. Metals are extracted from these insoluble bases-Carbonates- Sodium hydrogen carbonate (NaHCO3)-bicarb soda for cakes to rise, safely neturalise acids.Sodium carbonate (Na2CO3)- synthesised industrially for use in making