Flashcards in C2G - Why Do We Need Fertilisers Deck (23):
What are the three essential elements in fertilisers ?
What happens if plants don't get enough of the 3 essential elements ?
Their growth and life processes are affected
Why could elements be missing from the soil ?
They may have been used up by a previous crop
What do fertilisers do in terms of the elements ?
Replace missing ones
What do fertilisers increase ?
The crop yield
What must happen before the plant takes in the fertiliser ?
Dissolve in water
What's an advantage of fertilisers ?
More crops to help feed to increasing world population
Disadvantage of fertilisers ?
Risk of killing aquatic life and polluting our waters
What part does rain water play in the process of eutrophication ?
It washes excess fertilisers off the fields into rivers and streams
When fertilisers are washed into streams what happens ?
The level of nitrates and phosphates in the water increases
What happens to the algae in the waters ?
It uses the nutrients to multiply rapidly creating an algae bloom
Why is an algae bloom bad ?
It blocks off light to river plants below
Why do river plants below algae die ?
Can't access sunlight to photosynthesise
What do the aerobic bacteria do ?
Feed on the dead plants and multiply
What happens as the bacteria multiply ?
They use up all the oxygen
Why do many fish die as a result of eutrophication ?
The aerobic bacteria uses up their oxygen
What fertilisers can ammonia make ?
What method is used to make fertilisers ?
Step 1 of making a fertiliser is ?
Fill a buttered with an acid
What must you do with the alkali during the making of a fertiliser ?
Measure some using a measuring cylinder and add it to the conical flask
What else do you add to the conical flask ?
After you've added indicator what should you do?
Allow the acid to run from the bursts into the alkali until the indicator says its been neutralised