Organic Chemistry Flashcards
What are the properties of the homologous series?
- family of compound with similar chemical properties
- represented by a general formula
- show a gradual trend in physical properties e.g melting and boiling points
- always a diff of CH2 between one member and the next in the series
two examples of homologous series are:
- The alkanes
- The alkenes
What are all molecules in the alkanes and the alkenes?
Hydrocarbons
What are hydro carbons?
compound made of only hydrogen and carbon
What are the alkanes in terms of hydrocarbons
Saturated
definition of saturated?
Atoms are joined together by single covalent bonds
the aliens are what kind of hydrocarbon?
unsaturated
definition of unsaturated?
Chemical compounds that contain carbon-carbon double bonds.
When naming an alkane what must one remember?
-All alkanes end with the suffix -ANE
- the number of carbon atoms in the molecule is represented by a specific prefix
E.G. Methane, ETHane, PROPane, BUTane,PENTane, HEXane
What is the general formula for Alkanes?
CnH2n+2
^ the n represents the number of carbon atoms
What must one remember when naming an alkene?
- All alkenes end with the suffix -ENE
- By the number of C atoms in the molecule is represented by the same prefix as for the alkanes.
What is the general formula for Alkenes?
CnH2n
definition of an Isomer? (Do not confuse with isotope)
Isomers are molecules with the SAME MOLECULAR FORMULA BUT A DIFFERENT STRUCTURAL FORMULA.
Alkanes are unreactive molecules what does this mean?
they do not burn in air to produce carbon dioxide ad water and release energy
when do alkanes react with bromine?
in the pre scene of UV light
what is the word equation for the bromine and methane reaction? and what kind of reaction is it?
Methane+ Bromine= Bromoethane + hydrogen bromide.
-substitution reaction
why are alkenes reactive molecules?
Because they have a carbon carbon double bond
Why are alkenes not used as fuels?
They are to valuable
-used to make plastics
What do alkenes react with bromine to make a reaction occur?
React with bromine or bromine water and do not need uv light for this reaction to occur.
what kind of reaction is Alkene and bromine?
Addition reaction
What colour is bromine?
orange/brown
What is crude oil?
-it is a fossil fuel
a mixture of hydrocarbons of different sized
What is the process of distillation of crude oil?
- Crude oil is heated so it becomes a mixture of vapours.
- vapour pass in fractoining column where they cool.
- the different fractions cool at different temps because …
- defferent hydrocarbons have different sized molecules so diff boiling/condensing point.
what properties do the crude oil vapours at the top of the fractioning column have?
- low temperature (70C)
- small molecules condense
- light in colour
- runny (less viscous)
- very flammable
e. g. petroleum gases, petrol, kerosine
What properties do the crude oil vapours at the bottom of the fractioning column have?
- high temperatures (360C)
- large molecules condense
- dark in colour
- think and viscous
- difficult to light
Definition of boiling point?
the temperature at which the liquid boils or the gas condenses
definition of volatility?
The tendency to turn into a gas
definition of viscosity?
how easy it flows
Definition of flammability?
how easily it burns
what is the test for carbon dioxide?
turns limewater cloudy
what is the chemical test for water?
anhydrous colbot chloride paper turns from blue to pink
Physical test for water?
boils at 100C and freezes at 0
When does complete combustion occur?
When there is plentiful/sufficient supply of oxygen
When does Incomplete combustion happen?
if there is a limited/ insufficient supply of oxygen
what is a dangerous product of incomplete combustion?
Carbon monoxide
What is carbon monoxide?
a poisonous, colourless, tasteless, odourless gas.
why is carbon monoxide dangerous? (cause and effect)
- binds more easily to haemoglobin in the blood than oxygen
- carries around the body and reduced respiration
- leads to unconsciousness or even death
What is fermentation?
Conversion of sugars to ethanol
what conditions are needed for fermentation.
temp of about 35C- (above 40C the yeast would be denatured
- anaerobic conditions
- aqueous solution
What is the word equation for fermentation?
Glucose»»»»>ethanol + carbon dioxide
^^ yeast enzymes//35C
name a country which uses fermentation and reasons for it?
Brazil- have resources e.g. sugar beat +sugar cane.
climate is right, land and it can be produced v cheaply
