Unit 8 - Carbon Flashcards Preview

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Flashcards in Unit 8 - Carbon Deck (17)
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1
Q

Can you draw graphite

A

Yes? Good

2
Q

Why can graphite be used as a lubricant

A

The layers of graphite can slide over each other.

3
Q

Why is diamond used for cutting tools

A

It’s giant lattice structure and lack of free electrons means that it is very strong

4
Q

Why is carbon monoxide poisonous

A

It replaces the oxygen in the haemoglobin in your red blood cells, reducing the capacity of your blood to carry oxygen

5
Q

Why does the incomplete combustion of fuels produce carbon monoxide

A

Because it doesn’t finish reacting with the oxygen in the air to form CO2 instead of CO

6
Q

Describe the laboratory preparation of CO2 (metal carbonate)

A

Heat a metal carbonate. If a metal carbonate is heated it decomposes (not burn) evolving CO2 gas and leaving the metal oxide

7
Q

Thermal decomposition of a metal carbonate

A

Metal carbonate -heat-> metal oxide + carbon dioxide

8
Q

Describe the laboratory preparation of CO2 (acid + carbonate)

A

If a dilute acid is added to a metal carbonate in the cold, CO2 is produced
Eg CaCO3 + 2HCl –> CaCl2 + H2O + CO2

9
Q

What’s the purpose of concentrated sulphuric acid in the production of CO2 (acid + carbonate)

A

It is a drying agent (absorbs water)

10
Q

How can CO2 be collected

A

Downward delivery (it’s denser than air)
Using a gas syringe
Over hot water

11
Q

Is CO2 soluble in water

A

It’s fairly soluble in cold water, not very soluble in hot water

12
Q

CO2 + water

A

CO2 (g) + H2O (l) –> H2CO3 (aq)

Carbonic acid is fairly weak (pH5)

13
Q

Define an acid

A

An acid is a source of H+ ions

14
Q

Uses of CO2

A

In fizzy drinks

In fire extinguishers

15
Q

Why can CO2 be used in fizzy drinks

A

Because it is soluble in cold water so will stay dissolved in the drink until it reaches your warm mouth where it will fizz because CO2 is less soluble in warm water

16
Q

Why is CO2 used in fire extinguishers

A

Not flammable (only magnesium burns it it)
Denser than air, it forms a layer over the fire so O2 can’t reach it
Doesn’t conduct electricity

17
Q

Can you draw diagrams of diamond

A

Yes? Good.