Organic chemistry

Question 1

Hydrocarbons
What are Hydrocarbons ?
What is the simplest type of hydrocarbon you can get ?
What is alkanes general formula ?
The alkanes are saturated compounds,what does this mean?
What are the first four alkanes ?
What kind of series are the hydrocarbons ?

Answer 1

Any compound that is formed from carbon and hydrogen atoms only
Alkanes
CnH2n+2
Each carbon atom forms four single covalent bonds .
Meaning it has the maximum amount of hydrogens possible
All alkanes are a homologous ,meaning they all react in a similar way as they have similar properties
Methane,Ethene,Propane,Butane
monkeys eating peanut butter
M-1carbon,E-2 carbons
Homologous series ,all react in a similar way

Question 2

Properties hydrocarbon as length increases ?
Length
Three characteristics of Short hydrocarbons

Answer 2

Boiling point increases with chain length
longer they get the less volatile (evaporate less easily )
get more viscous as they get longer
less flammable as they increase in length

Question 3

What does the complete combustion of hydrocarbon release lots of?
What is the equation ?
What happens to carbon and hyrogen ?
Why are hydrocarbons used in fuels ?

Answer 3

Releases lots of energy
When there is a lot of oxygen
Hydrocarbon+oxygen-carbon dioxide +water
Carbon + Hydrogen are both oxidized
Hydrocarbons are used as fuels due to the amount of energy released when they combust completely.

Question 4

What is crude oil ?
What is it made up of explain?
Explain how Crude oil is formed

Answer 4

Crude oil is a fossil fuel
Made up of remains of plants/animals that died million of years ago and were burried in mud
over million of years with high temp ,pressure remains turn into crude oil

Question 5

What can be used to separate hydrocarbons
What is crude oil in terms of hydrocarbons ?
What is there in a column
What is the first step ?
What will condense Earlier and why ?
What will condense later and why ?
What does each fraction contain ?

Answer 5

Fractional distillation
Crude oil is a mixture of lots of different hydrocarbons(most alkanes )
There is a temperature gradient ,hotter at bottom,cooler at top
1)Oil is heated until most of it has turned into a gas,the gases enter the fractionating column
2)Longer chains have high boiling points ,condense into liquids and drain out early on (not hot enough to keep in gaseous form )
4)Shorter hydrocarbons have a lower boiling point meaning they condende and drain out towards end ,where it is cooler .
Each fraction contains a mixture of hydrocarbons that all contains similar number of carbon atoms

Question 6

Crude oil has various uses in Life
2 uses
What are all product of crude oil examples of ?
What is a homologous series?

Answer 6

Provides fuel for most transport (diesel oil,Kerosene,Petroleum)
The Petrochemical industry (feedstock,solvents,polymers,lubricants)
All products you get from crude oil
are examples of organic compounds(compounds containing carbon)
Groups that contain similar compounds with many properties in common

Question 7

What are short-chain hydrocarbons good for and why ?
-What does cracking do?
What does cracking produce?
What are products of cracking used for ?

Answer 7

Good fuels
short-chain hydrocarbons are flammable meaning they make good fuels and are high in demand
-longer alkane molecules are turned into smaller ones by using cracking
-cracking produces alkenes

Question 8

What kind of reaction is cracking ?
What are the two different kinds of cracking ?
What is the first step ?
First step for catalytic
How would you crack hydrocarbon using steam ?

Answer 8

Cracking is a thermal decompostion reaction(breaks down molecules by heating them up )
Catalytic and steam cracking
1)First we heat long-chain hydrocarbons to vaporize them .
2)The vapor is passed over a powdered hot allium oxide catalyst
3)Long chain splits into two -no molecules are lost
You would mix hydrocarbon vapor with steam and then heat them up to a very high temperature

Question 9

Alkenes
What are alkenes ?
Why are they unsaturated?
What are the first four alkenes?
Why do alkenes all react in a similar way
What do scientist call the double bond ?

What is the general formula for alkenes ?

Answer 9

Alkenes are hydrocarbons that have a double bond between two carbon atoms
Don’t have the maximum amount of hydrogen possible ,they have two less than alkanes but have same amount of carbon
Because of their double bond
Alkene functional group
Ethene,Propene,Butene,Pentene
Eating peanut butter power .
CnH2n

Question 10

What does functional group do ?
What do scientists call molecules with same functional group ?
Alkenes combustion
What do alkenes burn with?
What are the waste product of alkenes usually ?
What does incomplete combustion tend to result in ?
Energy,Flame ?

Answer 10

Determines how a molecule reacts
Part of same homologous serie
Alkenes burn with a smoky flame
hydrocarbon+oxygen-water+carbon dioxide
However, there isn’t enough oxygen in the air so when they burn they tend to undergo incomplete combustion.
carbon+carbon monoxide+carbon dioxide +water .
-smoky yellow flame ,less energy being released

Question 11

What is it called when hydrogen reacts with alkenes ?
what do you need in this reaction
What is produced when you react hydrogen with alkene

Answer 11

hydrogenation
nickel catalyst
alkane,as carbon double bond opens up

Question 12

What happens when alkenes react with halogens?
What are the molecules formed like?
How can you test for alkenes ?

Answer 12

Alkenes will react in additions reactions with halogens
molecules formed are staurated
Addition of bromine to a double bond
If its added to alkene than bromine will add across the double bond and make a colorless compound
otherwise, if it isn’t it will stay bright orange

Question 13

What happens when steam reacts with alkenes and why ?
What do you need in this reaction?
What is this reaction called ?
How do we increase the yield of ethanol?

Answer 13

Forms alcohols,as water is added to the double bond .
You have to pass it over a catalyst
Hydration
Any unreacted ethene and yield are passed back through the catalyst

Question 14

What are addition reactions

Answer 14

open up the double-bonded carbons to leave a single bond

Question 15

What are polymers made up of ?
What is an example of what polymer makes up ?
What are the two kind of polymers ?
In addition polymers what are the monomers ?
How do they become polymer chains ?

Answer 15

Polymers are made up of monomers that join together this is called polymerization.
plastics are made from polymers
Addition polymers and condensation polymers
Addition polymers -the monomers are alkenes (have a double covalent bond )
They open up their double bond and join together to form polymer chains

Question 16

What do all alcohols contain?
First 4 ?
Equation
What do the first 4 have that is similar?

Answer 16

All alcohols contain OH group
Methanol, Ethanol, Propanol,Butanol
C nH 2n+1OH
First four have similar properties

Question 17

What kind of combustion do alcohols undergo?
What are the products ?
In water ?
What does it form when oxidized?

Answer 17

They are flammable, Undergo complete combustion in the air to produce Co2 and water.
All soluble in water ,and Solutions has a neutral PH
Can be oxidized by reacting with oxygen forming carboxylic acid.

Question 18

What are alcohols used as ?2)

Answer 18

Solvents-they can dssolve most things that water cab and more (eg hydrocarbons and fats )
Fuel (first four are )

Question 19

What other way can ethanol be made ?
How does this work?
What is the word equation ?
What else is also produced ?
When does fermentation happen fastest?

Answer 19

Fermentation
Uses an enzyme in yeast to convert sugars into ethanol
Sugar-ethanol+carbon dioxide
Aqueous
Carbon dioxide is also produced
Fermentation happens fastest at temperatures around (37) and in slightly acidic solution and no oxygen .

Question 20

What are carboxylic acid made up of ?
what do their names end in ?

Answer 20

Carboxylic acids are made up of the homologous series that all have the same functional group
the names end in anoic acid eg methanoic acid

Question 21

What do carboxylic acids react with?
What do they produce
How do their salts end in ?
In water?
What kind of solutions do they form and why ?

Answer 21

They react with carbonates to produce salt ,water and carbon dioxide like all other acids
salts formed end in anoate eg ethanoate .
Can dissolve in water ,they dissolve and ionise and release H+ions
However don’t completely ionize (not all acid molecules release h+ions) ,they just form weak acidic solutions

Question 22

How are esters formed ?
What are esters functional group ?
What is used in this chemical reaction ?

Answer 22

Carboxylic acids +alcohol
esters have the functional group COO
Acid catalyst is used

Question 23

What number of types of monomers are there in condensation polymers ?
What happens for each new bond that is formed?
How many products are formed here ?

Answer 23

one monomer type with two different functional groups
two monomer types with same functional group .
For each new bond that forms a small molecule is lost
two types of products are formed

Question 24

Amino acids . How many functional groups does Amino contain, what are they called?
What is the smallest type of amino acid called ?

Answer 24

Amino acids have two different functional groups (Amino group )(carboxyl group )
smallest simplest type of amino acids is glycine

Question 25

What do amino acids form?
What group reacts with what other group?
What is one or more long chain of polypeptide known as ?
Polypeptides and proteins can contain different ?

Answer 25

amino acids can from polymers known as polypeptides via condensation polymerisation
amino group reacts with acid group ,for every bond that is formed a water molecule is lost.
One or more long chains of polypeptides is known as proteins.
Polypeptides and proteins can contain different amino acids in their polymer chains.

Question 26

What kind of structure does DNA a molecule have?

Answer 26

DNA is a large molecule that takes double helix structure .
DNA is made of two polymer chains called nucletoids .The nucleotides each contain a small molecule known as a base -ACGT .

Question 27

simple sugars

Answer 27

sugars are small molecuels that contain hyrogen,carbon,oxygen
react together through polymerization reacts togethere to form larger carbohydrate polymers