Organic Chemistry

Question 1

What bonds do alkanes have?

Answer 1

C-C single bonds

Question 2

Alkane general formula

Answer 2

CnH2n+2

Question 3

What is a homologous series?

Answer 3

A group of organic compounds that react in a similar way

Question 4

Alkanes are saturated compounds. What does that mean?

Answer 4

Each carbon atom forms 4 single covalent bonds

Question 5

What are the first 4 alkanes?

Answer 5

Methane, ethane, propane, butane

Question 6

The shorter the chain length what happens to the viscosity?

Answer 6

Less viscous

Question 7

The shorter the chain length what happens to the volatility?

Answer 7

More volatile, gas at a lower temperature, lower boiling point

Question 8

The shorter the chain length what happens to the flammability?

Answer 8

More flammable

Question 9

What are ‘bottled gasses’

Answer 9

Gasses stored under high pressure as liquids in bottles, happen to short-chain hydrocarbons

Question 10

Hydrocarbon complete combustion equation

Answer 10

Hydrocarbon + oxygen –> carbon dioxde + water (+energy)

Question 11

What is crude oil and how is it formed?

Answer 11

A fossil fuel, the remains of plants and animals that died millions of years ago and were buried in mud, high temperature and pressure, remains turn to crude oil, drilled from the rocks which is where its found

Question 12

What is crude oil and how is it separated?

Answer 12

A mixture of different hydrocarbons and by fractional distillation

Question 13

How does fractional distillation work?

Answer 13

.Oil is heated to a gas
.Gas enters a fractioning column
.Hot at the bottom and cool at the top (temperature gradient)
.Long chain lengths have high boiling points so condense quickly and drain out at the bottom
.The shorter chain lengths have lower boiling points so condense and drain out much later at the top where its cooler
.You end up with a crude oil mixture that has been separated into different fractions

Question 14

What is LPG?

Answer 14

Liquid petroleum gas

Question 15

What is cracking and why do we do it?

Answer 15

Splitting up long chain hydrocarbons, we do it to get smaller chain lengths as they are more useful

Question 16

What type of reaction is cracking?

Answer 16

Thermal decomposition - breaking down molecules by heating them

Question 17

Describe how to catalytic crack

Answer 17

.Heat long chain hydrocarbons to vaporize them
.Vapour is passed over a hot powdered aluminum oxide catalyst
.The long chains split apart on the surface of the catalyst - this is catalytic cracking

Question 18

Describe how to steam crack

Answer 18

.Heat long chain hydrocarbons to vaporize them
.Mix them with steam
.Heat them to a very high temperature
.This is steam cracking

Question 19

Word equation for cracking?

Answer 19

Long chain hydrocarbon –> shorter alkane + alkene

Question 20

What type of bonds do alkenes have?

Answer 20

One C=C double bond

Question 21

Are alkenes saturated or unsaturated?

Answer 21

Unsaturated

Question 22

What are more reactive alkanes or alkenes? Why?

Answer 22

Alkenes, their C=C bond can open up to form a single bond and allow the carbon molecules to bond with other atoms

Question 23

Name the first 4 alkenes

Answer 23

Ethene, propene, butene and pentene

Question 24

Alkene general formula

Answer 24

CnH2n

Question 25

State the standard equation for the incomplete combustion of alkene

Answer 25

alkene + oxygen --> carbon + carbon monoxide + carbon doxide + water (+ energy)

Question 26

What will you see from the incomplete combustion of alkenes? What will you get energy wise?

Answer 26

Smoky yellow flame | Less energy than complete combustion

Question 27

What is a functional group?

Answer 27

A group of atoms in a molecule that determines how that molecule typically reacts

Question 28

What is the alkene functional group?

Answer 28

C=C

Question 29

What type of reactions do alkenes usually undertake?

Answer 29

Addition reactions

Question 30

What is hydrogenation?

Answer 30

The addition of hydrogen

Question 31

Describe the process and product of hydrogenation

Answer 31

Hydrogen can react with the double bonded alkenes to open up the double bond and form the equivalent alkane, it is reacted in the presence of a catalyst

Question 32

How do alkenes react with halogens?

Answer 32

In the same way as hydrogen, the C=C bond is broken and each atom in the covalently bonded halogen each takes one bond

Question 33

Ethene + bromine -->

Answer 33

Dibromoethane

Question 34

Why DI in them name Dibromoethane?

Answer 34

Two bromine atoms

Question 35

Why ethane in the name dibromoethane?

Answer 35

Saturated

Question 36

What color does bromine water turn if mixed with an alkene? Why?

Answer 36

Colorless, as the bromine will add across the double bond making a colorless dibromo-compound, decoloring it

Question 37

What do you add to alkenes to form alcohols?

Answer 37

Steam

Question 38

How can ethanol be made?

Answer 38

Mixing ethene with steam and passing it over a catalyst

Question 39

When making ethanol from ethene industrially what happens after the reaction has taken place?

Answer 39

The reaction mixture is passed from the rector into the condenser, ethanol, and water both condense as they have a higher boiling point and unreacted ethene gas is recycled back into the reactor. The alcohol can then be purified from the mixture by fractional distillation

Question 40

What is a polymer?

Answer 40

A long molecule formed when lots of monomers join together, this reaction is called polymerization

Question 41

What conditions does polymerization need?

Answer 41

High pressure and a catalyst

Question 42

What are plastics made of?

Answer 42

Polymers, usually from carbon-based alkene monomers

Question 43

What is addition polymerization?

Answer 43

Lots of unsaturated molecules can open up their double bonds and join together to form polymer chains

Question 44

What does the 'n' on a displayed formula of an addition polymer mean?

Answer 44

It shows there is a number of monomers

Question 45

How do you get the polymer name from the monomer? Use Propene as an example

Answer 45

Put the word 'poly' in front of the monomer name and but the monomer name in brackets - poly(propene)

Question 46

Alcohol general formula

Answer 46

CnH2n+1OH

Question 47

Alcohol functional group

Answer 47

-OH

Question 48

Name first 4 alcohols

Answer 48

Methanol, ethanol, propanol, butanol

Question 49

What is the naming system?

Answer 49

The same as the alkanes but replace the final 'e' with an 'ol'

Question 50

Why is CH3OH correct but CH4O not?

Answer 50

It shows the -OH functional group

Question 51

Describe the first 4 alcohols

Answer 51

``` .Flammable .Undergo complete combustion .Soluble in water with neutral pH .React with sodium to produce hydrogen .Oxidised to produce carboxylic acid ```

Question 52

What is methanol and ethanol used as?

Answer 52

Solvents in industry, they can dissolve most things water can dissolve plus hydrocarbons, oils, and fats

Question 53

What are the first 4 hydrocarbons used as? Example

Answer 53

Fuels, ethanol is used as a fuel in spirit burners - burns fairly clean and is non-smelly

Question 54

Which alcohol is the one in wine and beer?

Answer 54

Ethanol, usually made via fermentation

Question 55

Describe the process of fermentation

Answer 55

Fermentation uses an enzyme in yeast to convert sugars into ethanol, carbon dioxide is also produced, a reaction occurs in a solution so the ethanol produced is aqueous

Question 56

Word equation for fermentation

Answer 56

Sugar --> yeast --> ethanol + carbon dioxide

Question 57

Best conditions for fermentation

Answer 57

37'C Slightly acid Anaerobic conditions (no oxygen)

Question 58

The functional group of carboxylic acids

Answer 58

-COOH

Question 59

How do carboxylic acids get their name? and name the first 4

Answer 59

The names end in 'anoic' and start with the normal starters | methanoic acid, ethanoic acid, propanoic acid, butanoic acid

Question 60

What does the functional group look like structurally?

Answer 60

A Carbon atom double bonded to an Oxygen atom and singly bonded to a hydroxide molecule

Question 61

What does a carboxylic acid produce when it reacts with carbonates?

Answer 61

a salt, water and carbon dioxide

Question 62

Ethanoic acid + sodium carbonate -->

Answer 62

sodium ethanoate + water + carbon dioxide

Question 63

How do you name the salts produced in carboxylic acids reactions with carbonates?

Answer 63

the end in 'anoate'

Question 64

Why do carboxylic acids form weak acidic solutions? How does this compare them to strong acids of the same concentration?

Answer 64

When they dissolve in water and ionize by releasing the H+ ions they don't ionize completely (not all the acid molecules releases their H+ ions), so they have a higher pH than other acids of the same concentration

Question 65

Esters functional group

Answer 65

'-COOH-'

Question 66

How are esters formed? (word equation)

Answer 66

alcohol + carboxylic acid --> acid catalyst --> ester + water

Question 67

What acid catalyst is usually used?

Answer 67

Concentrated sulfuric acid

Question 68

Ethanoic acid + ethanol --> acid catalyst -->

Answer 68

Ethyl ethanoate + water

Question 69

What does condensation polymerization involve?

Answer 69

Monomers that contain different functional groups

Question 70

What do the monomers do in condensation polymerization?

Answer 70

.React and form bonds, making polymer chains .For each new bond that forms a small molecule, for example, water is lost which is why it's called condensation polymerization

Question 71

Ethane diol + hexanedioic acid -->

Answer 71

a polyester + water

Question 72

A diol + a dicarboxylic acid -->

Answer 72

condensation polymer + water

Question 73

What functional groups do amino acids have?

Answer 73

a basic amino group (NH2) and an acidic carboxyl group (COOH)

Question 74

What is the smallest and simplest amino acid?

Answer 74

Glycine

Question 75

What can amino acids form through condensation polymerization?

Answer 75

Polymers known as polypeptides

Question 76

What do long chains of polypeptides make?

Answer 76

proteins

Question 77

What gives proteins their different polymers and shapes?

Answer 77

The order of amino acids

Question 78

What is DNA made of?

Answer 78

Two polymer chains of monomers known as 'nucleotides'

Question 79

What do sugars contain?

Answer 79

They are small molecules that contain carbon, hydrogen, and oxygen

Question 80

What can sugars do?

Answer 80

React together through polymerization reactions to form larger polymers