C10 - Organic Reactions 2️⃣✅ Flashcards
What is a functional group?
An atom or group of atoms withina molocule that have siimilar chemical properties whenever it appears in various compounds
What is a homogulous series?
A family of hydrocarbons with similar chemical properties who share the same general formula
What is an alkene?
A class of hydrocarbons & unsaturated compounds with at least one carbon-to-carbon double bondA class of hydrocarbons & unsaturated compounds with at least one car
What is an addition reaction?
An organic reaction in which 2 or more molocules combine to generate a bigger one
What is the general formula for alkenes?
CnH2n
Where ‘n’ is the number of carbon atoms in the substance
What does volatile mean?
Volatile means that the substance is easily evapourated at room temperature
What is a weak acid?
An acid that once reacted, doesnt produce 100% H+ ions
What is a strong acid?
An acid that once reacted, produces 100% H+ ions
How do you test for alkanes/ alkenes?
Bromene water
If it stays orange = alkane
If it turns colourless = alkene
What is the functional group for carboxylic acids?
-COOH
What is the functional group for esters?
-COO-
What is the functional group for alcohols?
-OH
What is the prefix of a substance that contains 1 carbon atoms?
meth_____
What is the prefix of a substance that contains 2 carbon atoms?
eth_____
What is the prefix of a substance that contains 3 carbon atoms?
prop_____
What is the prefix of a substance that contains 4 carbon atoms?
but_____
What is the prefix of a substance that contains 5 carbon atoms?
pen_____
What is the prefix of a substance that contains 6 carbon atoms?
hex_____
What is the prefix of a substance that has double bonds?
____ene
What is the prefix of a substance that has single bonds?
____ane
What is the prefix of a substance that is in the alcohol functional group?
____ol
What is an unsaturated compound?
A substance that contains at least one double or triple bond
What is the functional group for an alkene?
C=C
(the carbon-carbon double bond)
How are alkenes formed?
Cracking
How are alcohols formed?
Fermentation
How are carboxylic acids formed?
The oxidation of alcohols
What does saturated mean?
That there are no double bonds, only single
What are some common uses for alcohols?
- hand sanatziser
- alcoholic drinks
- perfumes
- aftershaves
What is the organic product of a reaction betweena carboxylic acid and an alcohol?
an ester
Name the first 4 alcohols
- menanol
- ethanol
- propanol
- butanol
Name the first 4 carboxylic acids
- methanoic aicd
- ethanoic acid
- propanoic acid
- butanoic acid
Name the first 4 alkenes
- methene
- ethene
- propene
- butene
Are alkenes saturated or unsaturated compounds?
unsaturated because they have 1 double bond
Each displayed formula for alkenes has ________ ____ bond?
Each displayed formula for alkenes has 1 double bond
Why can alkenes undergo addition reactions?
Due to them having a carbon to carbon double bond; it can open up and allow the 2 carbons to bond to atoms of another molelcule
What are the 3 main types of addition reactions?
- With hydrogen
- With water
- With Halogens
What are the conditions of addition reactions with water?
- presence of a catalyst
- high temperatures
Why are high temperatures required for addition with water?
So the water will be as water vapour (steam)
What happens during additon reaction with water?
- Upon reacting the alkenes carbon-carbon double bond opens up
- Water molecule then splits from h20 (2 hydrogen 1 oxygen) into one hydrogen atom and an O-H group
- These both then bind to the 2 spare carbon atoms
- Product due to O-H group = alcohol with hydrocarbon prefix e.g. ethene –> ethanol
- Have to separate ethanol from unreacted ethene and unreacted water
- To remove unreacted ethene, cool the mixture causing the ethanol and water to condense to a liquid, therefore leaving ethene as a gas & removing it
- To then remove unreacted water from the desired ethanol we have to use fractional distillation (heat mixture, ethanol will boil as ethanol low BP, this will cause it to evapourate up column and condense down condenser into pure ethanol, separating it from water)
What are the conditions of addition reactions with hydrogen?
- presence of a catalyst
What are the conditions of addition reactions with halogens?
No conditions, no catalyst or specific temp etc
How does addition reaction with hydrogen work?
- react alkene with hydrogen atoms (h2) in presence of catalyst
- this breaks down the alkenes double bond, allowing for the two hydrogens to bond to the newly avainable carbon atoms
- Forming the alkane equivalent to the initial alkene e.g. ethene —> ethane
What is the general formula for alcohols?
CnH2n+1OH
What are 3 properties of alcohols?
- flammable
- soluble
- oxidised to form carboxylic acids
What are the 3 main uses for ethanol?
- biofuel
- alcoholic drinks
- chemical feedstock to produce other organic compounds
What is the general formula for carboxylic acids?
CnH2n+1COOH
What type of acid is carboxylic acids?
Weak acids
Upon ionisation, for example, what would propanoic acid produce?
A propanoate ion and a hydrogen ion
prexfix = ‘anoate’ up ionisation of carboxylic acids
What happens when a carboxylic acid reacts with a carbonate?
produces a salt, water & carbon dioxide
What are the conditions for the fermentation of alcohols?
- carried out in fermentation tanks
- requires yeast cells
- has to be between 30-40 degrees for enzymes to work at optimum
- has to be anerobic conditions (no oxygen) as the reaction is anerobic respiration
What happens when alchols react with sodium, dissolve in water, react with an oxidising agent and burn in air?
- reacts with sodium to form a salt. When alcohols react with sodium, a salt will be formed plus hydrogen; bubbles of hydrogen gas will be seen (sodium reacting with ethanol produces sodium ethoxide)
- will dissolve in water to form a solution with a neutral pH (7)
- when reacted with an oxidising agent they produce carboxylic acids
- when burning in air they undergo complete combustion
What happens when a carboxylic acid dissolves in water & also what happens when they react with alcohol?
- upon dissolving in water they form acidic solutions with pH values less than 7
- upon reacting with alcohols carboxylic acids produce esters
What is are 2 properties of esters?
- pleasant spell
- volatile
What are esters most commonly used for?
- perfumes
- food colourings
How is ethyl ethanoate produced?
By reacting ethanoic acid with ethanol
What is this the displayed formula of? + explain and state fomula for this substance
ethyl ethanoate
CH3COOC2H5
combination of:
ethanoic acid: CH3COOH
annd
ethanol: C2H5OH
but without the OH from ethanoic acid and the ‘H’ from OH on the ethanol; those 3 produce a water molecule (h20) and that is a biproduct of the reaction
What acid catalyst is used when reacting a carboxylic acid and an alochol together to produce an ester?
Concentrated sulphuric acid