fertilisers and crop yields Flashcards
how does a plant get its elements?
taking in minerals from its roots
who do fertilisers increase crop yield?
because they contain all the essential elements plants need
what are the 3 essential elements?
nitrogen, phosphurus and potassium
what are fertilisers called that contain these essential elements?
NPK
what is eutrophication?
when farmers need to be certain that fertilisers dont run off land into streams or lakes which can kill aquatic animals
what is the only way plants can obtain essential elements?
if the compound dissolves in water
why is there no point in putting fertilisers into pure elements?
because they need to be turned into chemical compounds
it takes a while for essential elements to dissolve
remember
what do protein molecules contain?
nitrogen atoms
what does a plant need nitrogen for?
to grow
explain the process of eutrophication?
plants photosynthesise producing oxygen. fish need oxygen to survive
nitrate or phosphate run off into the river. Sunlight cant reach the plant so dont produce oxygen
plants at bottom die. fish die due to lack of oxygen dissolved fertilisers make algae grow on surface, algal bloom
what is a fertiliser that contains nitrogen called?
nitrogenous fertiliser
name 4 nitrogenous fertilisers
amonium phosphate
ammonium nitrate
ammonium sulfate
urea
what do you make when you react sulfuric acid and ammonia?
ammonium sulfate
how do you make crystals using an alkali and acid?
.titrate the alkali with the acid using an indicator
.repeat the titration until consistant results
.this makes a neutral solution of ammonium sulfate, but it is contaminated with indicator
.using titration result to add the correct amounts of acid and alkali with the indicator
.evaporate using a hot water bath
leave to crystalise
filter off crystals
