Organic Chemistry (C)

Question 1

what are the first four hydrocarbons

Answer 1

-methane
-ethane
-propane
-butane

Question 2

what is a hydrocarbon

Answer 2

molecules made up of carbon and hydrogen atoms only

Question 3

what is crude oil

Answer 3

finite resource
remains of ancient biomass like planktons burried in the mud in rocks
filled with compounds like hydrocarbons

Question 4

general formula of alkanes

Answer 4

CnH2n+2

Question 5

what are saturated bonds

Answer 5

single bonds c-c

Question 6

what are unsaturated bonds

Answer 6

double bonds c=c

Question 7

what is incomplete combustion

Answer 7

when the fuel doesn’t burn properly and doesn’t have enough oxygen, it forms carbon monoxide, carbon, soot/particulates

Question 8

fractional distillation

Answer 8

-crude oil is a mix of hydrocarbons
-F>D used to separate crude coil into more useful substances
-Difference sized hydrocarbons have different boiling points
-crude oil is heated in fractionating columns, hotter at the bottom and cooler at the top
-vapour rises up the column and condenses when cool enough
-liquid is collected at the different columns

Question 9

hydrocarbon properties

Answer 9

• low bpt at the top, flammable, low viscosity
  -high bpt at bottom, not so flammable, high viscosity

Question 10

pollutants made from burning fuels

Answer 10

-carbon dioxide
-carbon monoxide
-particulates
-nitrogen oxide
-sulphur dioxide

Question 11

issues pollutants make

Answer 11

CO2 - global warming
CO - death
Particulates - global dimming
NO - acid rain + respiratory issues
SO2 - acid rain + respiratory issues

Question 12

what are alkenes

Answer 12

unsaturated hydrocarbons

Question 13

what are alkanes

Answer 13

saturated hydrocarbons

Question 14

general formula for alkenes

Answer 14

CnH2n

Question 15

first four alkenes

Answer 15

ethene
pentene
butene
propene

Question 16

how to detect alkenes and alkanes
(bromine water)

Answer 16

orange bromine water added to alkene will go colourless
orange bromine water added to alkane will stay the same

Question 17

two types of cracking

Answer 17

Catalytic cracking - adding a catalyst + high temp
Steam cracking - increasing temperature + steam

Question 18

what is cracking

Answer 18

process of breaking down hydrocarbons to gain smaller and more useful molecules

Question 19

what does cracking make?
ENE and ANE

Answer 19

Alkenes and Alkanes

Question 20

difference with alkanes and alkenes

Answer 20

alkenes are unsaturated, alkanes are saturated
alkenes are more reactive and are more useful

Question 21

why do we crack hydrocarbons

Answer 21

because we have more larger hydrocarbon chains which aren’t as useful as the smaller hydrocarbon chains