C2G - Why Do We Need Fertilisers Flashcards Preview

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Flashcards in C2G - Why Do We Need Fertilisers Deck (23):
0

What are the three essential elements in fertilisers ?

Nitrogen
Phosphorus
Potassium

1

What happens if plants don't get enough of the 3 essential elements ?

Their growth and life processes are affected

2

Why could elements be missing from the soil ?

They may have been used up by a previous crop

3

What do fertilisers do in terms of the elements ?

Replace missing ones

4

What do fertilisers increase ?

The crop yield

5

What must happen before the plant takes in the fertiliser ?

Dissolve in water

6

What's an advantage of fertilisers ?

More crops to help feed to increasing world population

7

Disadvantage of fertilisers ?

Risk of killing aquatic life and polluting our waters

8

What part does rain water play in the process of eutrophication ?

It washes excess fertilisers off the fields into rivers and streams

9

When fertilisers are washed into streams what happens ?

The level of nitrates and phosphates in the water increases

10

What happens to the algae in the waters ?

It uses the nutrients to multiply rapidly creating an algae bloom

11

Why is an algae bloom bad ?

It blocks off light to river plants below

12

Why do river plants below algae die ?

Can't access sunlight to photosynthesise

13

What do the aerobic bacteria do ?

Feed on the dead plants and multiply

14

What happens as the bacteria multiply ?

They use up all the oxygen

15

Why do many fish die as a result of eutrophication ?

The aerobic bacteria uses up their oxygen

16

What fertilisers can ammonia make ?

Ammonium sulphate
Ammonium nitrate

17

What method is used to make fertilisers ?

Titration

18

Step 1 of making a fertiliser is ?

Fill a buttered with an acid

19

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

20

What else do you add to the conical flask ?

Indicator

21

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

22

What do you need to do to get solid crystals ?

Gently evaporate the solution until only a little bit is left and leave it to crystallise