Unit 3-Chemistry in Society Flashcards Preview

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Flashcards in Unit 3-Chemistry in Society Deck (43)
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1
Q

What are the main properties of metals

A

Metals are malleable, they conduct electricity and they have a high melting point

2
Q

What does oil rig stand for?

A

Oxidation is loss and reduction is gain

3
Q

Describe metallic bonding

A

The atoms are held together by an electrostatic attraction between the positive nucleus and the delocalised electrons

4
Q

What are rare earth metals used for?

A

Computers, laptops, mobiles, tablets and GPS

5
Q

Name two rare earth metals

A

Neodymium and dysprosium

6
Q

How do you break down metal ores which are below copper on the reactivity series?

A

You can break them down by heating them up

7
Q

How do you break down the metal ores which are situated above mercury but below aluminium in the reactivity series?

A

By mixing them with carbon and then reacting them with oxygen

8
Q

How do you break down the metal ores which are situated above zinc in the reactivity series?

A

By electrolysis

9
Q

What is redox reaction

A

Redox reaction occurs when electrons are lost by one substance during oxidation and are gained by another substance during reduction

10
Q

How can you predict the voltage output when two metals are connected together using an electrolyte?

A

By their position on the electrochemical series, the larger the gap, the larger the voltage output

11
Q

In an electrochemical cell, what is used to connect the two solutions?

A

An iron bridge/salt bridge

12
Q

In an electrochemical cell, what direction does the electrons flow?

A

The electrons flow from the metal electrode which is higher up in the electrochemical series to the metal electrode lower down in the electrochemical series. If both electrodes are the same element then the metal in the solution indicates the electron flow.

13
Q

What is the difference between thermosoftening and thermosetting plastics?

A

Thermosoftening plastics soften when heat is applied

14
Q

What is the definition of a non-biodegradable plastic

A

It doesn’t naturally break down

15
Q

What happens when you burn a plastic?

A

Carbon monoxide is given off

16
Q

What happens when you burn poly vinyl chlorine?

A

Hydrogen chloride is given off

17
Q

What happens when you burn polyurethane?

A

Hydrogen cyanide is given off

18
Q

Name two plastics and their uses

A

Kevlar-body armour

Poly(ethanol)- used in PVA glue

19
Q

What are the two types of polymerisation?

A

Addition and condensation polymerisation

20
Q

What is the polymer name of ethene?

A

Poly(ethene)

21
Q

How do you identify if a polymer has been created through condensation or addition polymerisation?

A

If it’s a condensation polymer it will have oxygen in its main carbon chain

22
Q

What is the repeating unit?

A

The part of a polymer which is repeated

23
Q

What are monomers?

A

Monomers are small molecules which join together to form the polymer and normally are unsaturated

24
Q

Name two natural polymers

A

Rubber and silk

25
Q

What is a polyester?

A

A plastic formed by a carboxylic acid and an alcohol

26
Q

What gets produced in condensation polymerisation?

A

Water

27
Q

Where does the H20 come from in condensation polymerisation?

A

The OH comes from the alcohol and the O comes from the carboxylic acid

28
Q

What two compounds are traditionally used when creating a polyester?

A

Diols and dicarboxylic acids

29
Q

What is a novel material?

A

A material that doesn’t resemble anything that has previously been made

30
Q

What is corrosion?

A

Corrosion is a chemical reaction which occurs on the surface of a metal

31
Q

What happens during corrosion?

A

The metal element is reacting to form a metal compound

32
Q

Rusting can only occur to which metal?

A

Iron

33
Q

What conditions are needed for iron to rust?

A

Water and oxygen need to be present

34
Q

What is used to test for rust?

A

Ferroxyl indicator, the yellow liquid will turn blue

35
Q

What are smart materials?

A

Smart materials are compounds which can be changed through external stimuli

36
Q

What is an alloy?

A

An alloy is a MIXTURE of metals which haven’t reacted together

37
Q

What is brass made out of?

A

Copper and zinc

38
Q

What is stainless steel made out of?

A

Iron and carbon

39
Q

Why do we need fertilisers?

A

To replenish the soil with nutrients that the plants use to grow, which we can eventually feed on

40
Q

What are the three main elements in fertilisers?

A

Nitrogen, Potassium and Phosphorus

41
Q

Why is NPK in an ionic compound?

A

Because it needs to dissolve in water for the plants to absorb it

42
Q

What can fertilisers cause by irresponsible usage?

A

Eutrophication and algal blooms

43
Q

Describe the Haber process

A

Nitrogen and hydrogen are reacted and put in a compressor, the solution then moves into a catalyst chamber and then to a condenser. The ammonia is extracted and the recycled reactants are then put back into the catalyst chamber to reduce waste.