paper 2

• fuel oil is used as fuel for ships
• kerosene is used for fuel for planes
• bitumen is used for road surfacing
• catalytic cracking is the name of the process used to convert long-chain molecules into more useful and shorter-chain molecules
• fermentation needs to be anerobic as if not the ethanol will react with oxygen to male the carboxylic acid, ethanoic acid. in aerobic conditions carbon dioxide and water is produced. the temperature needs to be below 40C so that the enzymes in the yeast aren't denatured.
• when preparing esters a small amount of concentrated sulphuric acid is used as a catalyst to speed up the reaction
• esters are scented, have a fruity smell therefore they are used in perfumes are flavourings
• methyl orange is red in acids and yellow in alkalis
• litmus paper is red in acids and blue in alkalis
• when testing for hydrogen gas you use a lit split and it will give a squeaky pop
• when testing or oxygen it relights a glowing splint
• crystallization is used in separating a soluble solid from a liquid
• to obtain a soluble solid from a liquid you heat the solution to evaporate some of the water form the solution then cool the mixture then filter the mixture then leave it in a warm dry place to dry
• ionic bonding is between a metal and a non-metal, transfer of electrons. they have a strong attraction between positive and negative ions, so more energy is needed to break them, they have a high melting point. they conduct electricity while a liquid or a solution as the ions can move.
• there are two types of covalent bonding, simple molecular and giant covalent
• covalent bonds are non-metals that are sharing electrons
• simple molecular bonding has intermolecular forces. they have a low melting point due to the weak intermolecular forces. these forces are easy to overcome
• giant covalent bonds have a very high melting point due to the lots of strong covalent bonds
• graphite has weak forces between layers so they can easily slide over each other. graphite also has delocalized electrons between layers which can conduct electricity
• covalent bonding is the attraction between shared pairs of electrons and the two nuclei
• Solvent- The liquid in which a solute dissolves
• Solute- The substance which dissolves in a liquid to form a solution
• when testing for ammonium red litmus paper turns blue when warmed with NaOH
• hydroxide is used in testing for Cu(II) and Fe(II/III), ion responsible for alkali
• sulphate produces a white precipitate with barium chloride and nitric acid
• hydrogen a lit splint gives a pop
• thermal decomposition is the breaking down of a compound into simpler substances by heating
• all nitrates are soluble
• all chlorides soluble except silver and lead
• all sulphates are soluble except barium, calcium and lead
• all carbonates are insoluble except sodium, potassium and ammonium
• all hydroxides are insoluble except sodium, potassium and calcium
• the molecular formula for methane is CH4
• the molecular formula for ethane is C2H6
• the molecular formula for propane is C3H8
• the molecular formula for butane is C4H10
• the molecular formula for pentane is C5H12
• the molecular formula for hexane is C6H14
• the molecular formula for heptane is C7H16
• the molecular formula for octane is C8H18