Hydrocarbons

Question 1

What is the functional group of Alkenes?

Answer 1

The carbon double bond

Question 2

What are isomers?

Answer 2

Molecules with the same molecular formula but different arrangements of atoms

Question 3

What is the bromine water test?

Answer 3

Bromine water has an orange-brown colour
When it is mixed with Alkenes, a chemical reaction occurs leading to colourless products.
Alkanes do not cause decolorisation so this is a good test to determine if something is an Alkane or Alkene

Question 4

Why does this test work?

Answer 4

The double carbon bond reacts with the bromine to form a colourless product.
Therefore, the bromine is removed from the solution so it loses its colour
Alkanes don’t have a double carbon bond

Question 5

What is an addition reaction?

Answer 5

A reaction in which reactants combine to form one larger product molecule and no other products.

Question 6

How do you name the single product in addition reactions?

Answer 6

Add ‘di-‘ to the beginning if diatomic
It’s 1.1 if the atom e.g. bromine, is attached to one carbon atom.
If it’s attached to two, it’s 1.2 and so on

If it’s by itself, it’s 1 - (name) if it’s on the first carbon
2 - (name) if it’s on the second carbon

And so on

Question 7

What is the ethanol in alcoholic drinks made from?

Answer 7

Sugars

Question 8

What family of substances do sugars belong to?

Answer 8

Carbohydrates

Question 9

Are these sugars soluble or insoluble?

Answer 9

Soluble

Question 10

Why are fruit used frequently in alcoholic drinks?

Answer 10

Fruit contains a lot of sugars

Question 11

What do seeds contain?

Answer 11

Starch

Question 12

What needs to happen to starch before it can be used in alcoholic drinks?

Answer 12

Must be broken down into sugars

Question 13

What must happen to the seeds before using them?

Answer 13

Must be germinated

Question 14

What happens during this process?

Answer 14

Enzymes in the seeds turn the starch into sugars

Question 15

What plant is commonly used in beer?

Answer 15

Barley seeds

Question 16

What plant is commonly used in wine?

Answer 16

Grapes

Question 17

What plant is commonly used in whiskey?

Answer 17

Barley seeds

Question 18

What plant is used in vodka?

Answer 18

Wheat seeds

Question 19

What is fermentation?

Answer 19

When plant material contains sugars (e.g. glucose) it is mixed with water and yeast at 25 degrees and turns it into ethanol and carbon dioxide

Question 20

What are the conditions for fermentation?

Answer 20

Temperature and pH of the solution must be carefully controlled

Oxygen must be kept out of container as yeast fermentation is an example of anaerobic respiration (doesn’t require oxygen)

Question 21

Why is fermentation only used on weak(er) drinks?

Answer 21

Fermentation produces drinks up to 15% alcohol content

Anymore, and the higher concentrations kill the yeast cells

Question 22

How are higher concentrated solutions produced?

Answer 22

Fractional distillation
I,e, Boiling point of ethanol is 78 degrees.
The first fraction collected will contain a higher percentage of alcohol

Question 23

What is the function group of alcohols?

Answer 23

-OH

Question 24

What are the similar chemical properties of alcohols?

Answer 24

Produce carbon dioxide and water on complete combustion

Can be oxidised to form carboxylic Acids

React with reactive metals such as sodium, which forms hydrogen gas

Question 25

What is the Core-Practical for The combustion of Alcohols?

Answer 25

1) Measure the mass of an alcohol burner and cap. Record the mass and the name of the alcohol. 2) Place the alcohol burner in the centre of a heat-resistant mat 3) Use a measuring cylinder to add 100cm cubed of cold water to a conical flask 4) Measure and record the initial temperature of the water and clamp the flask above the alcohol burner 5) Light the wick of burner and allow the water to heat up to 40 deg. 6) Replace the cap on burner and measure and record final temperature of the water 7) Measure the mass of alcohol burner and cap again and record the mass 8) Calculate the mass of alcohol burned to produce a 1 deg.rise in temperature. 9) Reapeat using different alcohol and fresh cold water

Question 26

What are the first four carboxylic Acids?

Answer 26

Methanoic acid Ethanoic acid Propanoic acid Butanoic acid

Question 27

What are the similar chemical properties of carboxylic Acids?

Answer 27

They all: - Form solutions with a pH lower than 7 (if soluble) - React with metals to form a salt and hydrogen - React with bases to form a salt and water - React with carbonates to form a salt, water and carbon dioxide

Question 28

How can vinegars be used to test for carbonate rocks e.g. limestone?

Answer 28

The ethanol acid fizzes producing carbon dioxide

Question 29

How are carboxylic Acids produced?

Answer 29

When alcohols are oxidised All weak Acids

Question 30

What does the functional group of carboxylic Acids, form when in a solution?

Answer 30

Hydrogen ions

Question 31

What is the functional group of carboxylic Acids?

Answer 31

= o -c \o - h

Question 32

What are monomers?

Answer 32

A single small molecule

Question 33

What is a polymer?

Answer 33

A long chain molecule made of many monomers

Question 34

What are the two types of polymerisation ?

Answer 34

Addition polymerisation | Condensation polymerisation

Question 35

What is addition polymerisation?

Answer 35

A type of polymerisation where the monomers add on to each other and no small molecules are eliminated Process happens again and again forming a long chain

Question 36

What is used to show this repeating chain?

Answer 36

Repeating unit

Question 37

How do you name a polymer of any monomer?

Answer 37

Poly (monomer) E.g. polymer of Ethene Poly (Ethene)

Question 38

Why is poly (Ethene) a synthetic polymer?

Answer 38

It is manufactured in a laboratory or factory

Question 39

What are some naturally occurring polymers?

Answer 39

Proteins - polymers from amino acids | Starch - polymer from sugar

Question 40

What are the properties and uses of poly(Ethene)?

Answer 40

Flexible, cheap, good insulator Uses: Plastic bags, plastic bottles, cling film, polytunnels

Question 41

What are the properties and uses of poly(propene)?

Answer 41

Flexible, does not shatter Uses: Buckets, bowls, crates, ropes and carpets

Question 42

What are the properties and uses of poly(chloroethene)?

Answer 42

Tough, good insulator, can be made hard or flexible Uses: window frames, gutters, pipes, insulation for electrical wires

Question 43

What are the properties and uses of PTFE : poly(tetrafluoroethene)?

Answer 43

Tough and slippery Non-stick coatings on pans, kitchen utensils (non-stick), stain proofing carpets and clothes

Question 44

What is condensation polymerisation?

Answer 44

Where monomers join together and eliminate a small molecule I.e. water (create it as a by-product)

Question 45

What is the functional group for esters?

Answer 45

``` O / -C \\ O ```

Question 46

How are esters formed?

Answer 46

Carboxylic Acid + alcohol = ester + water

Question 47

What are Ester links?

Answer 47

They are the two functional groups (alcohol and carboxylic acid) at the end of each of the molecules. Must have 2 functional groups to form a long chain

Question 48

Why are using monomers to make synthetic polymers a problem?

Answer 48

They are obtained from crude oil which is a non-renewable source.

Question 49

Why is the synthetic polymers not being biodegradable a good and bad thing?

Answer 49

Good: Last for long time Bad: Do not break down/rot when thrown away

Question 50

How can burning plastics (synthetic polymers) be a bad thing? And good?

Answer 50

Burning releases energy which can be converted to electricity However, burning emits greenhouse gases like carbon dioxide Some even produce toxic substances when burnt

Question 51

How can we prevent this?

Answer 51

Reuse plastic bags | Help conserve supplies of crude oil - stop making more and just reuse

Question 52

Why is it difficult to recycle polymers?

Answer 52

Collect the waste Sort the waste into different types of polymers - done by hand -expensive. Dispose of waste that can’t be recycled Clean polymers and grind them into chippings Purify the chippings Melt the chippings then process into new product