16. Fertilisers

Question 1

What 3 elements are needed for plant growth?

Answer 1

Question 2

Why must N P and K be in th forms they are and not as elements?

Answer 2

Elemental forms are not soluble in water and can’t be taken up by roots

Answer 3

Question 4

What is a fertiliser?

Answer 4

A soluble salt containing one or more of

N (as NO₃^- ions)

P (as PO₄^3- ions)

K (as K⁺ ions)

Question 5

How are salts made?

Answer 5

By neutralising acids with bases.

Question 6

What is the molecular formula for ammonia?

Answer 6

NH₃

Question 7

What shape is the ammonia molecule?

Answer 7

Trigonal pyramidal

Question 8

Show how the outer electrons are shared in an ammonia molecule

Answer 8

Question 9

What are the properties of ammonia?

Question 10

What is the equation for the reaction of ammonia with water

Answer 10

Question 11

What is the chemical test for ammonia?

Answer 11

Turns damp pH paper blue

Question 12

What is the balanced equation for the formation of ammonia from elements?

Answer 12

Question 13

Haber process diagram

Answer 13

Question 14

What is the catalyst in the Haber process?

Answer 14

Iron (Fe)

Question 15

What is the temperature and pressure in the Haber Process

Answer 15

Temp: 450ºC

Pressure: 200 atmospheres

Question 16

What is the name of process to make Nitric Acid?

Answer 16

Ostwald Process

Question 17

What is the catalystr used in the Ostwald Process?

Answer 17

Platinum

Question 18

What is the temperature in the Ostwald Process?

Answer 18

850 ºC

Question 19

What are the 3 steps in the Ostwald Process?

Answer 19

1. Catalytic oxidation of Ammonia to form Nitrogen Monoxide
2. Oxidation of Nitrogen Monoxide to form NO₂
3. Reaction of NO₂ with water and oxygen to form Nitric Acid

Question 20

What is eutrophication?

Answer 20

The introduction of excess nutrients to a water system