level: npk fertilisers
Questions and Answers List
level questions: npk fertilisers
| Question | Answer |
|---|---|
| why might farmers decide to use formulated fertilisers over manure | -more widely available -easier to use -dont smell -just enough of each nutrient so more crops can be grown |
| what are the three main essential elements for fertilisers and why might these elements be missing from the soil | -nitrogen, phosphorus, potassium -they could be missing if they've been used up by a previous crop |
| how do fertilisers increase crop yield | replacing missing elements or providing more of them which means crops can grow faster and bigger |
| ammonia reacts with what to produce nitric acid | oxygen and water |
| why might ammonium nitrate be the most popular fertiliser, give the symbol equation for ammonium nitrate | -it has nitrogen from two different sources -NH3 + HNO3 --> NH4NO3 |
| why can't phosphate salts in phosphate rock be used as nutrients for plants | they are insoluble |
| reaction with nitric acid and phosphate rock | phosphoric acid and calcium nitrate |
| reaction with sulphuric acid and phosphate rock | calcium sulfate and calcium phosphate (mixture known as single superphosphate) |
| reaction with phosphoric acid and phosphate rock | calcium phosphate (triple superphosphate) |
| what are some sources of potassium | mining potassium chloride and potassium sulphate |