testing for water | Copper (II) sulphate: Anhydrous or ‘dehydrated’ (and pure) copper (II) sulphate is white. When water is present in anhydrous copper(II) sulphate it turns blue, becoming hydrous copper (II) sulphate |
testing for water | Cobalt (II) chloride: Anhydrous or ‘dehydrated’ (and pure) cobalt (II) chloride is blue. When water is present in anhydrous cobalt (II) chloride it turns pink, becoming hydrous cobalt (II) chloride. |
purifying water | Filtration: The different sized insoluble particles are filtered out of the water using filters |
purifying water | Chlorination: Chlorine is injected into the water and it sterilises it, killing the microbes |
percentages of the things in clean air | 78% nitrogen, 21% oxygen and small quantities of noble gases, water vapour and carbon dioxide. |
what are the common pollutants in air | carbon monoxide, sulphur dioxide and nitrogen oxides |
where does carbon monoxide come from | incomplete combustion of carbon-containing substances, |
why is carbon monoxide bad | carbon monoxide poising : causes breathing problems as it reduces the amount of red blood cells in the body |
where does sulphur dioxide come from | combustion of fossil fuels which contain sulphur compounds |
what does sulphur dioxide lead to | lead to acid rain which corrodes metal, erodes stone work and can kill plants and aquatic life. |
whre does nitrogen oxides come from | car engines |
what does nitrogen oxide potentially lead to | react with other pollutants to form smog which causes difficulty in breathing. It also causes acid rain. |
what can a catalyic converter do (for the bad stuff) | used to remove nitrogen monoxide and carbon monoxide from exhaust emissions through the reaction over a hot catalyst. |
what can be carbon monoxide be oxidied to | become carbon dioxide. 2CO + O2 → 2CO2 |
what can nitrogen monoxide be reduced to | nitrogen and oxygen. 2NO → N2 + O2 |
conditions for rusting of iron. | The presence of oxygen and water vapour in air |
how can rusting be stopped | by encasing the metal with paint, oil, grease or coating with plastic |
how can rusting be stopped | sacrificial protection, implementing the reactivity scale |
examples of sacrificial protection | iron can be coated (galvanised) with zinc as zinc is more reactive than iron, and it oxidises more readily than the iron. After the sacrificial metal has been corroded then it can be replaced. |
how can be carbon dioxide get formed | as a product of complete combustion of carbon-containing substances |
how can be carbon dioxide get formed | as a product of respiration |
how can be carbon dioxide get formed | as a product of the reaction between an acid and a carbonate |
how can be carbon dioxide get formed | as a product of thermal decomposition of calcium carbonate |
what type of gas is carbon dioxide and methane | greenhouse gases |
what is nitrogen, phosphurus and potassium needed for | fertilisers as they provide the mineral ions required for healthy growth in plants |
fertlisers must be | soluble in water so that the root hair cells in the plants can absorb the ions. |
how do we create ammonia | habor process, reversible reaction |
factors of ammonia | 450 degrees |
factors of ammonia | 200 atmopheres |
factors of ammonia | iron catalyst |
process (picture) of habor process | here |