Organic Chemistry 2 Flashcards
Define polymerisation
The process of creating/producing a long chain of molecules from small molecules
Define addition polymerisation
How monomers can join together to form very long chain molecules called polymers
Define monomer
The small molecules that add together to make a polymer are called monomers. These are alkenes
What is a polymer
Large organic molecules formed when smaller molecules join together in long chains.
What are the properties of polythene
Light, flexible and resistant to attack by acids and alkalis
What are the uses of polythene
Cling film, plastic bags, bottles, buckets and basins
Properties of PVC
Tough, durable, waterproof and a good insulator
Uses of PVC
Electric cables, guttering, drain pipes, umbrellas and window frames
What are the benefits of plastics
Less dense than other materials
Resistant to chemicals and water
Excellent insulator properties
Extremely long lasting
Inexpensive
What are disadvantages of plastics
Addition polymers are non-biodegradable (not decomposed by bacteria in the environment)
Surplus of plastics littering our oceans
Kills aquatic life
What are the advantages of landfill
Cheap and easy
Local treatment so less transport needed
Land can be reused after
What are the disadvantages of landfill
Wastes land
Takes a long time to break down
Polluting gases released
What are the advantages of incineration
Heat energy can generate electricity
Less waste going to landfill
What are the disadvantages of incineration
Releases polluting gases
Ash residue is toxic
Costly to build and maintain
What is the general formula of alcohol
CnH(2n+1)OH
What are the 4 alcohols you need to know
Methanol
Ethanol
Propan-1-ol
Propan-2-ol
What is the molecular formula of methanol
CH3OH
What is the molecular formula of ethanol
C2H5OH
What is the molecular formula for propan-1-ol and propan-2-ol
C3H7OH
What are the observations for the combustion of alcohol
A clean blue flame and heat is released
What is the equation for the complete combustion of alcohol
Alcohol + oxygen —> carbon dioxide + water
What is the equation for the incomplete combustion of alcohol
Alcohol + oxygen —> carbon monoxide + water
How is alcohol produced using fermentation
A sugar solution is mixed with yeast in warm conditions in the absence of oxygen. The reaction produces carbon dioxide and ethanol. The reaction is brought about by the enzyme, zymase which is presents in yeast.
What is the equation for fermentation
Glucose —> carbon dioxide + ethanol
(Enzyme in yeast)
How else can ethanol be produced
Hydration of Ethene with steam. (Hydration reaction)
What is the equation of the hydration of Ethene with steam to produce ethanol
Ethene + water (steam) —> ethanol
(Phosphoric acid catalyst)
What happens when alcohols are oxidised by air
Mild oxidisation which will form carboxylic acids. E.g if wine is left standing it will be oxidised to ethanoic acid by the oxygen and the wine is turned into wine vinegar. Vinegar is a solution of ethanoic acid
How are alcohols oxidised by acidified potassium dichromate
Acidified potassium dichromate solution is an oxidising agent which oxidises some alcohols to carboxylic acids on warming
What observations can be seen when acidified potassium dichromate solution reacts with alcohols
The acidified potassium dichromate changes from orange to green when it oxidise alcohols
What is the general formula for carboxylic acids
CnH(2n+1)COOH
What are the 4 carboxylic acids you need to know
Methanoic acid
Ethanoic acid
Propanoic acid
Butanoic acid
What is the molecular formula of methanoic acid
HCOOH
What is the formula for ethanoic acid
CH3COOH
What is the formula for propanoic acid
C2H5COOH
What is the molecular formula for butanoic acid
C3H7COOH
Why are carboxylic acids weak acids
They only partially ionise in water
What are the observations when carboxylic acids react with sodium carbonate
Bubbles of gas formed, the white solid disappears and a colourless solution is formed
What is the general equation for carboxylic acid reacting with sodium carbonate
Carboxylic acid + sodium carbonate —> sodium salt + water + carbon dioxide
How can a carboxylic acid be distinguished from other organic compounds
Only carboxylic acids will release carbon dioxide when sodium carbonate is added to a sample. Gas can be identified by bubbling it through limewater and solution turning milky white.
What are the observations when a carboxylic acid reacts with magnesium
Bubble of gas are produced, heat is released, the grey solid disappears and a colourless solution is formed
What is the general equation for when carboxylic acids react with magnesium
Carboxylic acid + magnesium —> magnesium salt + hydrogen
What can be observed when carboxylic acid reacts with sodium hydroxide
Heat is released and the solution remains colourless
What is the general equation for carboxylic acids reacting with sodium hydroxide
Carboxylic acid + sodium hydroxide —> sodium salt + water
How are alkanes differentiated from other organic compounds
When reacted with bromine water it will change from orange/brown to colourless
Name common atmospheric pollutants
Carbon dioxide
Carbon monoxide
Soot (carbon particles)
Sulfur dioxide leading to acid rain
How is carbon dioxide formed and what problems can it cause?
Caused by complete combustion of hydrocarbon fuels.
CO2 is a greenhouse gas and leads to the greenhouse effect. Absorbs infrared radiation given off by the earth and causes the earths surface to warm leading to:
Sea level rises
Flooding
Climate change
How is carbon monoxide formed and what are the problems it can cause
Formed by incomplete combustion of fuels
Carbon monoxide is a toxic gas as it combines with haemoglobin in the blood, reducing its capacity to carry oxygen.
How is soot formed and what problems does it cause
Formed by incomplete combustion of fuels
The carbon particles pollute the air and can cause lung damage and respiratory problems
How is sulfur dioxide formed and what problems can it cause
Many fuels contain sulfur impurities which burn and produce acidic sulfur dioxide. The sulfur dioxide reacts with water in the atmosphere to form sulfurous acid which falls as acid rain
Acid rain can:
Damage buildings especially ones made of limestone
Damage vegetation
Kills fish in lakes and rivers
