Whats in Medicine? Flashcards
(31 cards)
What is the difference between a primary, secondary and tertiary alcohol?
Primary has one carbon connected to the carbon with the OH on
Secondary has two carbons connected to the carbon with the OH on
Tertiary has three carbons connected to the carbon with the OH on
What conditions are required for alcohol dehyrdation?
Alumina catalyst at 300*c
Describe the process and products of alcohol dehydration.
An alkane alcohol is dehydrated to make and alkene and water.
e.g.
C2H5OH ==> C2H4 + H2O
What type of inter-molecular bond do alcohols form between each other?
Hydrogen bonding
What happens when a primary alcohol is distilled with an oxidizing agent which is not in excess?
An aldehyde is formed
What happens when a primary alcohol is oxidized with the oxidisng agent in excess and refluxed?
A carboxylic acid is produced
What color does potassium dichromate change from and to?
Orange to Green
How do secondary alcohols oxidize and what are the conditions?
They oxidize to form a keytone. Under reflux. It does not oxidise further because a C-C Bond would have to be broken.
3 ways for esterification
Acid anhydride + alcohol ==> Ester + Carboxilic acid
Acid anhydride + Phenol ==> Ester + Carboxilic acid
Alcohol + Carboxilic acid ==> Ester + water
What are the conditions for esterification?
Concentrated sulfuric acid and carboxilic acid under reflux
Order the following in order of acidity (lowest to highest) water ethanol carboxilic acid phenol
ethanol
What happens when an alcohol reacts with water?
It makes: H3O+
R-OH + H2O ==>R-O- +H3O+
How does water react with water?
I makes H3O+
H2O + H2O ==> HO- + H3O+
What is iron chloride used to identify? and what happens?
Identifies phenols by changing colour to violet purple
What happens when a carboxilic acid or phenol reacts with a base?
It gives up the hyrdrogen in the OH group and that reacts with the OH in the base to form water. The metal from the base reacts with the left over oxygen.
Sodium hydroxide + Phenol ==> Benzene-ONa + H20
How can a bond deform? 3 ways
- Symmetric Stretch
- Asymmetric stretch
- Symmetric bend
What is the difference between symetric stretch and asymetric stretch?
symmetric stretch happens in oposite directions
asymmetric happens in the same direction
What is the fingerprint region in ir spectroscopy and how is it used?
It is the confusing part of the region and is hard to analyse so instead it can be compared to known samples to identify the compound.
How does Infra read spectroscopy work?
IR light is shone onto a substance and certain freqencies cause the moledule to
Why is carboxilic acid a good acid and alcohol isnt?
It is more stable having given away away hydrogen form the OH. Because the electrons spread around the two oxygen bonds.
What is green chemistry?
This is when you try and make a reaction better for the environment by reducing waste, reducing energy usage and making it safer. It often involves a better atom economy.
Describe the process for recrystalisation
It is used to purify a product by dissolving it in a chosen solvent and then filtering off the undissolved impurities. After cooling the desired dissolved compound. The dissolved product will crystallize leaving out and soluble impurities. The crystals can be washed.
How is melting point determination used?
This is used to check that a product is pure by finding its melting point. This is then compared with the known value. If they are the same then it is pure.
What is thin layer chromatography?
This is the process of testing to see if a sample is pure by dissolving it in a solvent and then letting it separate on a piece of silicone film
