Which water sample(s) will be investigated? What is the source of the water supply? How will the iron concentration be determined? If the iron concentration is too low it cannot be determined so how can the concentration be increased? Which chemicals will be required? What apparatus will be required? The hazards that might be involved and how you will minimise risk. Equipment and Materials Required ferric ammonium sulphate 2, 4, 6, 8 and 10 mol l-1 (see below × 10−5 standard solutions: for preparation) FeNH4(SO4)2•12H2O 1 mol l-1 ammonium thiocyanate solution 1 mol l-1 sulphuric acid (see below for preparation) 1 mol l-1 hydrochloric acid 100 cm3 beaker 200 and 500 cm3 volumetric flasks 5 cm3 pipette 100 cm3 conical flask Test tubes (5 for the references plus however many samples you are doing) Colorimeter & cuvettes distilled water Method Preparation Preparation of 1 mol l-1 ammonium thiocyanate solution Weigh 38 g of solid ammonium thiocyanate into a 500 cm3 volumetric flask and make up to the mark with distilled water. Preparation of Fe3+ standard solutions NB: It may take several days to dissolve the Fe3+ salt used here, so carry out this preparation well in advance of the rest of the experiment. Weigh out about 3.0 g of ferric ammonium sulphate Use a (FeNH4(SO4)2•12H2O). mortar and pestle to grind the salt to a fine powder. Accurately weigh 2.41 g of the
Which water sample(s) will be investigated? What is the source of the water supply? How will the iron concentration be determined? If the iron concentration is too low it cannot be determined so how can the concentration be increased? Which chemicals will be required? What apparatus will be required? The hazards that might be involved and how you will minimise risk. Equipment and Materials Required ferric ammonium sulphate FeNH4(SO4)2•12H2O standard solutions: 2, 4, 6, 8 and 10 × 10−5 mol l-1 (see below for preparation) 1 mol l-1 ammonium thiocyanate solution (see below for preparation) 1 mol l-1 sulphuric acid 1 mol l-1 hydrochloric acid 100 cm3 beaker 200 and 500 cm3 volumetric flasks 5 cm3 pipette 100 cm3 conical flask Test tubes (5 for the references plus however many samples you are doing) Colorimeter & cuvettes distilled water Method Preparation Preparation of 1 mol l-1 ammonium thiocyanate solution Weigh 38 g of solid ammonium thiocyanate into a 500 cm3 volumetric flask and make up to the mark with distilled water. Preparation of Fe3+ standard solutions NB: It may take several days to dissolve the Fe3+ salt used here, so carry out this preparation well in advance of the rest of the experiment. Weigh out about 3.0 g of ferric ammonium sulphate (FeNH4(SO4)2•12H2O). Use a mortar and pestle to grind the salt to a fine powder. Accurately weigh 2.41 g of the
Water_Analysis_Teacher_Technician.docx