Test 1 – Organic Chemistry

Question 1

Finite resources are

Answer 1

no longer being made or are being made much more slowly then they are being used. This means that they will run out

Question 2

Fossil fuels were formed from

Answer 2

biomass ( plankton and other living organisms) that sink to the sea flooor when they die. They are compressed over millions of years under layers of sediment and mud and form fossil fuels; coal, oil and natural gas

Question 3

feedstock

Answer 3

a raw material used to supply or fuel a machine or industrial process

Question 4

General formula of alkanes

Answer 4

CnH2n+2 where n is the number of carbon atoms in the molecule.

Question 5

Crude oil
is

Answer 5

a
finite
resource that is found in the Earth’s crust. It is the remains of
organisms
that lived and died millions of years ago - mainly plankton which was buried in mud.

Question 6

Crude oil is a ( structure wise)

Answer 6

complex
mixture
of hydrocarbons. The carbon atoms in these molecules are joined together in chains and rings

Question 7

Crude oil is an important source of:

Answer 7

fuels
such as petrol, diesel, kerosene, heavy fuel oil and liquefied petroleum gases

feedstock
for the
petrochemical
industry

Question 8

Other useful substances made from compounds found in crude oil include:

Answer 8

solvents

lubricants

detergents

Question 9

The
alkanes
form a

Answer 9

homologous series

Question 10

Like all homologous series, the alkanes:

Answer 10

have the same
general formula
differ by CH2 in
molecular formulae
from neighbouring
compounds
show a gradual variation in physical
properties
, such as their
boiling points
have similar chemical properties

Question 11

homologous series

Answer 11

A ‘family’ of organic compounds that have the same functional group and similar chemical properties.

Question 12

The alkanes are saturated hydrocarbons:

Answer 12

ydrocarbons
, because they are compounds containing hydrogen and carbon only

saturated
, because their carbon atoms are joined by C-C single bonds

Question 13

fractional distillation
is used

Answer 13

to separate
crude oil
into simpler, more useful
mixtures
. This method can be used because different
hydrocarbons
have different
boiling points
.

Question 14

During the fractional distillation of crude oil:

Answer 14

heated crude oil enters a tall
fractionating column
, which is hot at the bottom and gets cooler towards the top

vapours
from the oil rise through the column
vapours
condense
when they become cool enough
liquids are led out of the column at different heights

Question 15

Naming thing

Answer 15

my elephant poos bricks
methane
ethane propane and butane

Question 16

key points for small molecules in a fraction-ating column

Answer 16

low boiling points
very volatile
flows easily
ignites easily

Question 17

key points for big molecules in a fraction-ating column

Answer 17

high boiling points
not very volatile
doesnt flows easily
does not ignites easily

Question 18

Bitumen is used for

Answer 18

roads and roofs

Question 19

Heavy fuel oil is used for

Answer 19

fuel for some ships and power stations

Question 20

Diesel is used for

Answer 20

fuel for some cars and trains

Question 21

kerosene is used for

Answer 21

fuel for some air-crafts

Question 22

petrol is used for

Answer 22

fuel for cars

Question 23

liquified petroleum gases used for

Answer 23

fuel for domestic heating and cooking

Question 24

One way to remember the names of the fractions is:

Answer 24

Lazy Penguins Keep Drinking Hot Beer.
liquified petroleum
petrol
kerosene
Diesel
Heavy fuel oil
Bitumen

Question 25

Each crude oil fraction contains a mixture of ————– . The ———- in a fraction are mostly ———- called ———–

Answer 25

hydrocarbons repeat
alkanes

Question 26

Alkanes have similiar but not identical :

Answer 26

numbers of hydrogen and carbon atoms in their
molecules

boiling points
ease of
ignition

viscosity

Question 27

Hydrocarbon fuels can undergo——– combustion or ——- combustion depending on the amount of ——-available.

Answer 27

complete
incomplete
oxygen

Question 28

Complete combustion of a hydrocarbon fuel happens when there is a
andproduces

Answer 28

good supply of oxygen in air. Carbon and hydrogen atoms in the fuel react with oxygen in an
exothermic
reaction

fuel+O2-to co2 plus h20

Question 29

In complete combustion of a hydrocarbon fuel :

Answer 29

carbon dioxide
and water are produced

the maximum amount of
energy
is given out

Question 30

In a Bunsen burner,complete combustion occurs when

Answer 30

the air hole is fully open.

Question 31

complete combustion general word equation

Answer 31

hydrocarbon + oxygen → carbon dioxide + water

Question 32

Incomplete combustion happens when the supply of air or oxygen is —–. ——- is still produced, but ————–
and ———- are produced. ——— energy is released than during complete combustion.

In a Bunsen burner, incomplete combustion occurs when —————————

Answer 32

poor
water
carbon monoxide
carbon
less
the air hole is closed.

Question 33

Cracking
is a reaction in which

Answer 33

larger saturated
hydrocarbon

molecules
are broken down into smaller, more useful hydrocarbon molecules, some of which are unsaturated:

Question 34

explain the starting reactants and products of cracking

Answer 34

the original starting hydrocarbons are
alkanes
the products of cracking include alkanes and
alkenes
, members of a different
homologous series

Question 35

Various methods can be used for cracking,;

Answer 35

eg catalytic cracking and steam cracking:

Question 36

Catalytic cracking :

Answer 36

uses a temperature of approximately 550°C and a
catalyst
known as a zeolite which contains aluminium oxide and silicon oxide

Question 37

Steam cracking

Answer 37

uses a higher temperature of over 800°C and no catalyst

Question 38

Reasons for cracking
Cracking is important for two main reasons:

Answer 38

1. It helps to match the supply of
   fractions
   with the demand for them.
2. It produces alkenes, which are useful as
   feedstock
   for the
   petrochemical
   industry.

Question 39

The supply is—————————————————————— The demand—————————————————————————Very often of crude oil
produces more of the————— than can be —–, and less of the —————–than ————————————

Answer 39

how much of a fraction an oil refinery produces.

is how much of a fraction customers want to buy.

larger hydrocarbons
sold
smaller hydrocarbons
customers want

Question 40

How does cracking solve the supply and demand problem

Answer 40

Smaller hydrocarbons are more useful as
fuels
than larger hydrocarbons. Since cracking converts larger hydrocarbons into smaller hydrocarbons, the supply of fuels is improved. This helps to match supply with demand.

Question 40

Alkanes and alkenes both form ————————– of hydrocarbons, but:

Answer 40

homologous series
alkanes are saturated their carbon atoms are only joined by C-C single bonds
alkenes are unsaturated they contain at least one C=C double bond

Question 41

alkanes are saturated their carbon atoms are only joined by C-C single bonds
alkenes are unsaturated they contain at least one C=C double bond
as a result :

Answer 41

As a result, alkenes are more
reactive than alkanes. Alkenes can take part in reactions that alkanes cannot. For example, ethene molecules can react together to form poly(ethene), a
polymer because alkenes have a double bond which can break

Question 42

What is the order for complicated balancing equation questions?

Answer 42

MINHO:

This is the order of how to balance equations that are complicated

M Metals

I Polyatomic Ions

N Non Metals

H Hydrogen

O Oxygen

Question 43

Combustion of alkenes

Answer 43

• burn with a smokier, yellow (luminous) flame than alkanes
• Incomplete combustion is more common with alkenes
  -less energy efficient than alkanes, so do not make such good fuels
• do burn completely too

Question 44

viscosity

Answer 44

(how easily it flows) increases as the chain length increases-flows less easily

Question 45

Flammability

Answer 45

(how easily it burns) increases as chain length increases

Question 46

Test for unsaturation explained

Answer 46

if there is as an alkene there will be a positive test for unsaturation because the water will turn from colourless to orange showing that the unsaturated alkene has bonded with the bromine
if there is an alkane there will be a negative test for unsaturation because the water will remain colourless because the alkane is already saturated and thus cannot bond with the bromine water

Question 47

Thermal decomposition

Answer 47

is a chemical reaction that happens when a compound breaks down when heated.

Question 48

Thermal decomposition reactions usually occur at—————–this —— breaks the ——– down into —————————

Answer 48

very high temperatures , heat, substance, two or more substances

Question 49

thermal decomposition is an example of an ——— reaction this means that it ————————-
so ————– must constantly be supplied ———– reaction ——-

Answer 49

endothermic

gains energy from the surroundings
thermal energy
to keep
going

Question 50

naming thing for polymerisation

Answer 50

put the word poly in front of the monomers namr

Question 51

testing for alkenes

Answer 51

bromine turns from orange- to colourless

Question 52

why is carbon monoxide bad

Answer 52

toxic gas that binds to red blood cells oxygen cant reach around the body

Question 53

viscosity and flammabiity

Answer 53

first increases as chain length increases
second decreases