Crude Oil and Organic Chemistry Flashcards
(23 cards)
What is a hydrocarbon? 
A compound of hydrogen and carbon only
Define homologous series 
What do they have in common x3
Homologous series is a family of compounds with similar properties because they have similar bonding. The alkanes are the simplest homologous series. 
General formulae
Trends in physical properties
Similar chemical properties
Define isomerism 
Structural isomers have the same molecular formula but a different displayed (or structural) formula
What is crude oil?
A mixture of hydrocarbons 
Name the six names of the main fractions obtained from crude oil and their uses 
Refinery, gases, gasoline, kerosene, diesel fuel oil, bitumen
What is the trend in colour, boiling point and viscosity of the main fractions?
Colour- gets darker down column
Boiling point- gets higher down the column
Viscosity- gets higher (i.e thicker) down the column
What is a fuel?
A substance that when burned releases heat energy 
What are the possible products of complete an incomplete combustion of hydrocarbons with oxygen in the air? 
Complete- carbon dioxide, water
Incomplete- carbon monoxide, water, carbon, carbon dioxide
Why is carbon monoxide poisonous in terms of its effect on the capacity of blood to transport oxygen?
Combines with haemoglobin in the blood , preventing oxygen capacity in blood
In car engines, the temperature reached is ——— enough to allow ——— and——— to react, forming——— of———
In car engine, the temperature reached is high enough to allow nitrogen and oxygen from air, react forming oxides of nitrogen 
How does the combustion of some impurities and hydrocarbon fuels result in the formation of sulphur dioxide?
Sulfur- impurity in crude oil and other fossil fuels
When burns with oxygen it forms sulfur dioxide
How does sulphur dioxide and oxides of nitrogen contribute to acid rain?
Acidic non-metals oxides such as sulfur oxides and nitrogen oxides dissolving in rain water
Oxygen and sulfur form sulfur dioxide dissolves in water forming sulfurous acid, then reacts with oxygen forming sulfuric acid
Nitrogen and oxygen at high temps. reacts with form oxides of nitrogen, this reacts with more oxygen forming nitrogen dioxide, this dissolves in water and reacts with more oxygen forming nitric acid causing acid rain
What is a general formula for alkanes? 
CnH2n+2
Why are alkanes classified as saturated hydrocarbons?
They contain the maxi un possible number of hydrogen atoms for a given number of carbons
Name the first five unbranched alkanes
Methane, ethane, propane, butane and pentane
How to represent organic molecules using molecular formulae, general formulae, structural formulae, displayed formulae for C2H6
Molecular-C2H6
General-CnH2n+2
Structural-CH3-CH3
Displayed-
H H
| |
H-C-C-H
| |
H H
Describe how the industrial process of fractional distillation separates crude oil into fractions
-separate a mixture of liquids that have different boiling points
-mixture is heated, liquids with low boiling point evaporate + turn to vapour
-liquid with high boiling point remain liquid, vapour separated from liquid
-
What is required when an alkane reacts with bromine
UV light
Why is UV light required when alkanes react with bromine
Because the reaction in very slow, but it still happens slowly with UV
Alkanes are fairly un reactive as they are …
Saturated
What must they given lots of in order to react with bromine
Energy
When alkanes react with bromine what happens
A hydrogen atom is replaced by one bromine atom called a substitution reaction
Substitution reaction for methane (displayed, symbol, word)
H H
| |
H— H—H + Br—Br —> H—C—Br + H—Br
| |
H H
CH4 + Br2 —> CH3Br + HBr
Methane + bromine —> bromomethane + hydrogen bromide
