Grade 10 - Organic Chemistry

Question 1

What is Organic Chemistry?

Answer 1

Organic Chemistry is the Chemistry of Carbon-based Lifeforms. (We are carbon based lifeforms for example)

Question 2

What is a functional group?

Answer 2

A group of compounds that all have the same general reactivity and properties (e.g alkanes, alkenes and alcohol :D)

Question 3

What are the prefixes in Organic Chemistry?

Answer 3

Meth - 1 Carbon Atom
Eth - 2 Carbon Atoms
Prop - 3 Carbon Atoms
But - 4 Carbon Atoms
Pent - 5 Carbon Atoms
Hex - 6 Carbon Atoms
Hept - 7 Carbon Atoms
Oct - 8 Carbon Atoms
Non - 9 Carbon Atoms
Dec - 10 Carbon Atoms

Question 4

What is an alkane?

Answer 4

• Hydrocarbons, they only have Carbon and Hydrogen atoms
• Contain only single bonds
• end in -ane
• Theyre all pretty flammable lol

Question 5

Examples of Alkanes

Answer 5

Methane - Cow farts
Propane - Bunsen Burner
Butane - Lighters

You can tell that theyre alkanes because they all end in -ane

Question 6

What is the general formula for Alkanes?

Answer 6

CnH2n+2

Brainscape is kinda cringe ngl, check in your books if youre confused

Question 7

What is an Alkene?

Answer 7

• Hydrocarbons, they contain only Carbon and Hydrogen
• They contain a double bond between 2 Carbons1
• They all end in -ene

1 This also means that Methene cannot exist, as you would need at least 2 Carbon Atoms, and molecules starting with “Meth” have only 1 Carbon atom

Question 8

What is the general formula for Alkenes?

Answer 8

CnH2n

Question 9

What is an Alcohol?

Answer 9

• Consist of Carbons, Hydrogens, and one Oxygen in an OH Molecule
• The OH is always bonded to a C
• All of them are poisonous lol
• very delicious nom nom

Question 10

What is the general formula for Alcohols?

Answer 10

CnH2n+1OH

Question 11

What are the 2 ways Ethanol can be formed?

Answer 11

• Fermentation of Glucose (For Wine, Beer, etc.)
• The addition of steam (H2O) to Ethene. This is called Hydration (For disinfectants. perfumes, solvents, etc.)

Question 12

How do Alkanes react?

Answer 12

They don’t. theyre about as boring as physics. They do burn however

Question 13

What is complete combustion?

How does it happen & What does it produce?

Answer 13

Complete Combustion is when there is enough oxygen to burn, producing carbon dioxide and water vapor when something is burnt

CH4 (Ethane) + O2 –> CO2 + H2O

Question 14

What is incomplete combustion?

How does it happen & What does it produce?

Answer 14

Incomplete Combustion is when there isnt enough Oxygen to properly sustain a fire, producing Carbon Monoxide instead of Carbon Dioxide

CH4 (Ethane) + O2 –> CO (Carbon Monoxide) + H2O

Question 15

How do Alkenes react with Halogens?

Answer 15

Alkenes are generally very reactive due to being unsaturated. With Halogens in particular, Halogens only add onto the Alkene. For example, if you added Bromine(Br2) to Ethene(C2H4), you would get Dibromoethane(C2H4Br2)1. Also, an important thing to remember is that the double bond between the 2 Carbons break apart to bond with the extra atoms.

1 I think that it is Dibromoethane and not Dibromoethene, because it loses the double bond and pretty much every source I look up says Dibromoethane im not sure tho

Question 16

Where do alkanes and alkenes come from?

Answer 16

Fossil Fuels –> Crude Oil –> Alkanes –> Alkenes
Alkanes are turned into alkenes in a process called cracking

crack is great

Question 17

What is Cracking?

not the drug

Answer 17

Cracking is when you take a larger Alkane and usually turn it into a shorter Alkane and an Alkene using high temperature and a catalyst
e.g
C4H10(Butane) –> C2H4(Ethene) + C2H6(Ethane)
C4H10(Butane) –> C3H6(Propene) + CH4(Methane)
C4H10(Butane) –> C4H8(Butene) + H2(Hydrogen)1
The product of the cracking changes based on the amount of temperature, pressure and catalyst used

1Sometimes its just the Alkene version of the Alkane and some H2

Question 18

Some more examples of Cracking because why tf not

Answer 18

C8H18(Octane) –> C7H14(Heptene) + CH4(Methane)
C8H18(Octane) –> C5H10(Pentene) + C3H8(Propane)
C8H18(Octane) –> C8H16(Heptene) + H2(Hydrogen)
C8H18(Octane) –> 2 C4H8(Butene) + H2(Hydrogen)

Again, the products depend on the temperature, pressure and catalyst

Question 19

What are Polymers?

Answer 19

Polymers are chains of many small molecules (monomers) that all form a longer chain

Question 20

What are some examples of polymers?

Answer 20

• Natural: DNA, Proteins, Carbohydrates
• Synthetic: Plastic (PET, PP, Polystyrene etc.)

Question 21

How would you model/draw a Polymer?

Answer 21

You draw it by taking the repeating unit, putting it in brackets, and write an n in the bottom right, the n representing how often it repeats.
https://www.bbc.co.uk/bitesize/guides/z3v4xfr/revision/6
This link shows how to do it

Brainscape is still being cringe, so you have to copy and paste the link

Question 22

What is Fractional Distillation, and what is it used for?

Answer 22

Fractional Distillation is a way to separate different alkanes from crude oil by utilizing their different boiling points. Lower boiling point alkanes will evaporate earlier than higher boiling point alkanes, and so they are separated by evaporating at different points and to different degrees.

Question 23

What are the eight products of Crude Oil, in order and their approximate boiling points?

(nvm i was wrong we dont need boiling points lol)

Answer 23

1. Refinery Gas
2. Petrol
3. Naphtha
4. Kerosene
5. Diesel
6. Lubricant Oil
7. Fuel Oil
8. Bitumen

Question 24

What are the uses of the eight products of Crude Oil?

Answer 24

1. Refinery Gas - Bottled Gas
2. Petrol - Cars
3. Naphtha - Very important thingy for chemicals
4. Kerosene - Planes
5. Diesel - Cars but mostly Trucks
6. Lubricant Oil - Would you believe me if I said its used for Lubricants (also Wax)
7. Fuel Oil - Ships
8. Bitumen - Roads and Roofing