Chapter 8 - Organic Chemistry

Question 1

what are hydrocarbons

Answer 1

molecules made of only hydrogen and carbon atoms

Question 2

what are saturated hydrocarbons

Answer 2

contain single bonds

fully surrounded by atoms

Question 3

what are unsaturated hydrocarbons

Answer 3

multiple bonds between carbons

not fully surrounded by atoms

Question 4

what are cyclic compounds

Answer 4

molecules where carbon atoms are arranged in a ring

Question 5

what is the alkane formula

Answer 5

2n +2

Question 6

what are alkanes

qazwsx

Answer 6

single bonds between carbon atoms

go through combustion and substitution reactions

Question 7

what is the alkene formula

Answer 7

2n

Question 8

what are alkenes

qazwsx

Answer 8

a double bond between carbon atoms
start with ethene as first member
go through combustion and addition reactions

Question 9

what is the alkyne formula

Answer 9

2n-2

Question 10

what are alkynes

qazwsx

Answer 10

triple bond between carbon atoms
starts with ethyne as first member
combustion and addition reactions

Question 11

what is the aromatic series

Answer 11

a family of unsaturated, cyclic hydrocarbons. simplest member is benzene

Question 12

naming hydrocarbons

Answer 12

1. determine the longest chain of carbon atoms. this chain must contain the double, triple bond if present
2. number carbons starting from end closest to functional group, double bond, alkyl branch
3. name each branch by the prefix, number of carbons, and the -yl suffix. indicate what number they are on. if there a 2 identical molecules we say di-. this applies for all branches
4. indicate what number the multiple bond is on and place between name.

Question 13

what are condensed formulas

Answer 13

also known as semi structural formulas show the structure of molecules with letters

Question 14

when do you use brackets in a condensed formula

Answer 14

to show branches

when CH2 is continually repeated

Question 15

what are functional groups

Answer 15

a group with a common bond, atoms or group of atoms that give a molecules specific properties

Question 16

alcohols

Answer 16

function group = -OH = hydroxyl group 
ends with the suffix -ol

Question 17

Carboxylic acids

Answer 17

function group = -COOH = carboxyl group
ends with suffix -anoic acid

Question 18

properties of alcohols

Answer 18

high points (h bonding)

solubility decreases with size (non polar region grows)

reactions are combustion, esterification/condensation

Question 19

properties of carboxylic acids

Answer 19

high points (hydrogen bonding from -OH)

smaller molecules are soluble for same reason as alcohols

reactions are esterification/condensation

have a pungent odour

weak acidity

Question 20

esters

Answer 20

functional group= -COO = ester group
follows the format of ____yl _____anoate

first is no. of carbons in alcohol
second is in carboxylic acid

Question 21

What are fossil fuels

Answer 21

natural fuels derived from the fossil remains of living organisms, which have been altered by heat and pressure underground

Question 22

where do hydrocarbons come from

Answer 22

crude oil/petroleum

Question 23

how is crude oil formed

Answer 23

in ancient times, plant and animal life fell to the sea floor and became covered with sediment.

high pressure and temperature over millions of years converted the once living material into hydrocarbons.

Question 24

explain fractional distillation

Answer 24

the process of using a fractionating tower to separate different types of alkanes found in crude oil. petroleum is boiled to create gases which have different condensation temperatures. this roughly separates the different molecules as they cool at different temps in the tower.

Question 25

what is catalytic cracking

Answer 25

the cracking of alkanes is the process of breaking large useless hydrocarbons into smaller more useful ones. this can be done with high heat or catalysts.

Question 26

describe a complete combustion reaction

Answer 26

where there is a plentiful supply of oxygen
hydrocarbon + oxygen – carbon dioxide + water

characterised by a blue flame

Question 27

describe an incomplete combustion reaction

Answer 27

where oxygen is limited
hydrocarbon + oxygen – carbon or carbon monoxide + water

characterised by an orange flame

Question 28

what is the limewater test

Answer 28

the limewater test is where the products of a combustion reaction are fed by pipe into a calcium hydroxide solution. if carbon dioxide is present it creates a precipitate of calcium carbonate, turning there whole solution cloudy

Question 29

describe a substitution reaction

Answer 29

alkane + halogen – haloalkane + bi-product

in the presence of UV or high heat

Question 30

describe an addition reaction

Answer 30

double bonds are broken to bond to a new molecule.
there is never a bi-product

catalyst not needed as double bonds are already repelling…

Question 31

describe an esterification reaction

Answer 31

where an alcohol and carboxylic acid come together to form an ester with water as a bi-product. due to water loss, it is sometimes called a condensation reaction.

Question 32

properties of an ester

Answer 32

relatively low boiling point (dipole-dipole only)

strong smell