Topic 6: Reversible Reactions, Industrial Processes and Important Chemicals Flashcards

A*

1
Q

What is a reversible reaction?

A

A reaction which can go in reverse order as well.

The products of the reaction can react together to produce the original reactants.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is ammonia?

A

A clear, gaseous, alkaline compound of nitrogen and hydrogen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are 3 uses of ammonia?

A

Explosives
Cleaning products
Fertilisers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the test for ammonia gas?

A

Turns damp red litmus paper blue (as litmus paper detects acidity/alkalinity)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the test for ammonium ions?

A

Ammonium ions found in compounds like ammonium chloride.

Add sodium hydroxide and heat gently, producing ammonia gas.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the Haber Process used for?

A

To collect ammonia.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the Haber Process equation?

A

Nitrogen + hydrogen ⇌ ammonia

N₂ + 3H₂ ⇌ 2NH₃

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How is nitrogen obtained for haber process?

A

Found in air (78%=nitrogen)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How is hydrogen obtained for haber process?

A

Reacting natural gas (mostly methane) with steam, or from cracking fractions.
CH₄ + 2H₂O -> CO₂ + 2H₂

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the conditions for the haber process?

A

High temperature - 350 - 450°C
High pressure - 150 - 200 atm
Iron catalyst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What happens to unreacted nitrogen and hydrogen?

A

As it is a reversible reaction, it can be recycled.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why must we compromise for pressure conditions in the haber process?

A

Increasing = increased yield

Too high = expensive unsafe.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why must we compromise for temperature conditions in the haber process?

A

Increasing = decreases yield

too low = slow rate of reaction (reason for iron catalyst)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the contact process used for?

A

To collect sulfuric acid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the raw materials used in the contact process?

A

Sulfur
Air
Water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 4 stages to the contact process?

A
1. Sulfur burned in air 
Sulfur + oxygen -> sulfur dioxide (cause of acid rain)
S + O₂ -> SO₂
2. More oxygen added
sulfur dioxide + oxygen ⇌ sulfur trioxide
2SO₂ + O₂ ⇌ 2SO₃
3. Sulfuric acid added
Sulfur trioxide + sulfuric acid -> oleum
SO₃ + H₂SO₄ -> H₂S₂O₇
4. water then added
oleum + water -> sulfuric acid
H₂S₂O₇ + H₂O -> 2H₂SO₄
17
Q

What are 4 uses of sulfuric acid?

A

fertiliser
paints and dyes
dehydrating agent
car batteries

18
Q

What will happen when you add sulfuric acid to hydrated copper (II) sulfate?

A
Hydrated copper (II) sulfate = blue
adding sulfuric acid = white - anhydrous copper (II) sulfate
19
Q

What will happen when you react sulfuric acid with glucose?

A

Concentrated sulfuric acid + glucose -> carbon

Dehydrates glucose and only leaves pure carbon - black.

20
Q

What are in the most effective fertilisers?

A

Nitrogen (from ammonia compounds) because plants need it in order to produce proteins.
Phosphorus and potassium are also essential elements commonly found in fertilisers.

21
Q

What are 3 advantages of artificial fertilisers?

A

Increases crop growth
Increases crop yield
Better soil quality

22
Q

What are 3 disadvantages of artificial fertilisers?

A

Causes eutrophication - fertilisers pollute waterways
Causes blue baby syndrome
Turns the soil acidic