Acids, bases and salts The characteristic properties of acids and bases Acids turn blue litmus red. Acids have are pH 6 and below (the syllabus says that pH values will be integers, no decimals) Acid + metal → metal salt + hydrogen Acid + base (except carbonates) →...
Types of oxides (NOTE: this was the first question on the paper 3 in the mock exam) In general, metal oxides are basic, and non-metal oxides are acidic. Neutral oxides: are neither acidic nor basic, they are neutral for example carbon monoxide. Amphoteric oxides: e.g....
8.3 Preparation of salts Preparing salts in the lab (all on pages 124 and 125) Starting with a metal: Add excess metal to an acid When bubbling (hydrogen) stops the reaction is done Filter off excess metal (because a metal is a solid, except mercury) Starting with an...
8.4 Identification of ions and gases Aqueous cations: Test Ion Result Add a few drops of dilute sodium hydroxide solution. A precipitate will form. Cu2+ Pale blue precipitate Fe2+ Green precipitate Fe3+ Red-Brown precipitate Al3+, Zn2+, Ca2+ White precipitate Divide...
Reversible reactions Reversible Reactions ⇌ : reactions which can go both ways, depending on the conditions. Example: CuSO4.5H2O (blue) ⇌ CuSO4(white) + H2O (to get anhydrous you heat it, & to get the hydrated form, just add water) There are two types of...
Redox Oxidation Is Loss of electrons or the gain of oxygen, Reduction Is Gain of electrons or loss of oxygen. Remember OIL RIG. Redox reaction is a reaction where reduction and oxidation happen, where there is electron transfer. Reduction and oxidation must happen...
Factors affecting the rate of reaction are: -Concentration (pressure in gases): the higher the concentration of reactants is (higher pressure in gases) the faster the reaction will happen. This is because there is more chance of reactant particles colliding, so there...
Chemical reactions Collision theory: collisions are needed for a chemical reaction to take place & the successful collisions have enough energy, also known as activation energy, at the moment of impact to break the preexisting bonds and form all new bonds.