Mid Topic April

Question 1

What is the chemical reaction for the formation of corrosion?

Answer 1

Iron + water + oxygen → Hydrated (Iron) Oxide

Question 2

What is the sacrificial method in corrosion prevention?

Answer 2

A method where a more reactive metal (like zinc) is attached to a less reactive metal (like iron) to protect it from corrosion

Question 3

What happens to the more reactive metal in the sacrificial method?

Answer 3

The more reactive metal corrodes instead of the less reactive metal

Question 4

What is galvanising?

Answer 4

Coating a less reactive metal (typically iron or steel) with a layer of zinc

Question 5

What is a coating method in corrosion prevention?

Answer 5

Applying a protective layer to the surface of a metal to prevent exposure to moisture and corrosive substances

Question 6

List three examples of coating methods.

Answer 6

• Painting
• Plastic coatings
• Zinc coating

Question 7

What is the role of anhydrous calcium chloride in rust prevention?

Answer 7

Absorbs moisture from the air, creating a dry environment that prevents oxidation or rusting

Question 8

How does oil prevent rusting?

Answer 8

Acts as a barrier preventing oxygen from entering

Question 9

What is the effect of boiling water on rust prevention?

Answer 9

Removes dissolved oxygen, preventing rusting

Question 10

True or False: Anhydrous calcium chloride allows moisture to remain in the environment.

Answer 10

False

Question 11

Fill in the blank: The sacrificial method uses a more _______ metal to protect a less reactive metal.

Answer 11

reactive

Question 12

What causes rusting?

Answer 12

Exposure to air (oxygen) and water leads to rusting

Question 13

What essential minerals do fertilizers provide for plant growth?

Answer 13

Fertilizers provide mineral ions such as:
* Nitrogen
* Potassium
* Phosphorus

Question 14

How do plants absorb minerals from the soil?

Answer 14

Plants absorb mineral ions through their root hair cells from the water in the soil

Question 15

Why do farmers and gardeners add fertilizers to soils?

Answer 15

To freshen the concentration of mineral ions as it decreases over time

Question 16

What is the role of nitrogen in fertilizers?

Answer 16

Nitrogen is crucial for plant growth and leafy growth

Question 17

What function does potassium serve in plant fertilization?

Answer 17

Potassium helps transport nutrients which helps flowering and fruiting

Question 18

What is the role of phosphorus in fertilizers?

Answer 18

Phosphorus aids in root development, flowering

Question 19

What must fertilizer compounds be to be effective?

Answer 19

Fertilizer compounds must be soluble in water to be absorbed by root hair cells

Question 20

What ions supply nitrogen in fertilizers?

Answer 20

Ammonium ions (NH4+) supply nitrogen

Question 21

What ions provide phosphorus in fertilizers?

Answer 21

Phosphate ions (PO4^3-) provide phosphorus

They are vital for energy transfer in plants.

Question 22

What is the role of potassium ions in fertilizers?

Answer 22

Potassium ions (K+) are essential for nutrient transport and flowering

Question 23

What is the importance of ammonia in making fertilizers?

Answer 23

Ammonia is an alkali that produces ammonium ions during neutralization reactions

These ammonium ions are used in fertilizers for leafy growth.

Question 24

Fill in the blank: Fertilizers must be _______ in water to be absorbed by plants.

Answer 24

soluble

Question 25

True or False: Potassium is important for root development.

Answer 25

False ## Footnote Phosphorus is primarily responsible for root development.

Question 26

Why are NPK fertilizers used instead of animal manure in agriculture?

Answer 26

More nutrients and higher nutrient concentration * Widely available/easy to access * Easy to use Don’t smell

Question 27

How do you obtain phosphate rocks?

Answer 27

Mining ## Footnote Phosphate rocks are mined for their phosphorus content, which is essential for plant growth.

Question 28

Why can't plants absorb phosphate rocks?

Answer 28

They are insoluble ## Footnote Insoluble substances cannot be dissolved in a solvent, making them unavailable for plant uptake.

Question 29

What is the chemical equation for the Haber Process?

Answer 29

N2 + 3H2 → 2 NH3 + HEAT ## Footnote The Haber Process synthesizes ammonia from nitrogen and hydrogen gases.

Question 30

What type of reaction occurs in the Haber Process?

Answer 30

Exothermic reaction ## Footnote An exothermic reaction releases heat during the process.

Question 31

What catalyst is used in the Haber Process?

Answer 31

Iron catalyst ## Footnote The iron catalyst speeds up the reaction without being consumed.

Question 32

What is the source of nitrogen in the Haber Process?

Answer 32

Air (78% nitrogen) ## Footnote Nitrogen is abundantly available in the atmosphere.

Question 33

How is hydrogen obtained for the Haber Process?

Answer 33

From hydrocarbons (natural gas) ## Footnote Hydrogen is typically produced from natural gas through steam reforming.

Question 34

What are the conditions for the Haber Process?

Answer 34

High pressure and high temperature * Around 200 atmospheres * Around 450°C ## Footnote These conditions optimize the reaction rate and yield of ammonia.

Question 35

What happens to unreacted gases in the Haber Process?

Answer 35

Recycled back into the process ## Footnote Recycling unreacted gases improves efficiency and reduces waste.

Question 36

Why are alloys harder than pure metals?

Answer 36

They are arranged in layers with different sized atoms. The larger atoms disrupt these layers meaning more energy is required to allow the layers to slide over each other.

Question 37

What is the relationship between the purity of gold and its malleability?

Answer 37

Lower purity leads to higher malleability ## Footnote Alloys with lower gold content are often more malleable and durable.

Question 38

What are commonly used karats for gold in jewelry?

Answer 38

14k and 18k

Question 39

Process of The Haber Process

Answer 39

Nitrogen is extracted from the air and hydrogen is extracted from natural gases Nitrogen and hydrogen gases are compressed to high pressures (arand 200 amospheres) Gases are then heated to high temperatures (around 450°) Gases pass over on iron catalyst Gases react forming ammonia Mixture is cooled, ammonia is condersed and liquified, seperated from unreacted gases Any unreacted nitrogen and hydrogen gases are recycled back into the process