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CHEMISTRY PRACTICAL ASSESSMENT... need help (1 Viewer)
- Thread starter spackness
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*sarah*
Member
Esters are prepared by the condensation of an alkanol and an alkanoic acid. They are often used as perfumes, solvents and flavorings. Some esters also appear naturally.
Refluxing involves the use of a vertical water-cooled condenser. As a reaction mixture becomes hot the vapours are condensed and return to the mixture. Refluxing allows a higher temp to be achived without a build up of pressure or loss of volatile components.
It would take forever to explain the process. I'd suggest checking out ur textbook, or if u dont have one (which u should) go to ur library and check out some books there. This is not a topic thats hard to find info on. Also check out google or the csu site: http://hsc.csu.edu.au/chemistry/core/acidic/chem935/chem935net.html
If uve got any specific questions once uve checked for info, just ask them
Refluxing involves the use of a vertical water-cooled condenser. As a reaction mixture becomes hot the vapours are condensed and return to the mixture. Refluxing allows a higher temp to be achived without a build up of pressure or loss of volatile components.
It would take forever to explain the process. I'd suggest checking out ur textbook, or if u dont have one (which u should) go to ur library and check out some books there. This is not a topic thats hard to find info on. Also check out google or the csu site: http://hsc.csu.edu.au/chemistry/core/acidic/chem935/chem935net.html
If uve got any specific questions once uve checked for info, just ask them
get conquering chem (HSC course). It explains it very well.
- Esterification: is the process of producing an ester by reacting an alkanol and an alkanoic acid in the presence of a sulfuric acid catalyst.
Generally:
Alkanol + alkanoic acid ---------> ester + water
the sulfuric acid catalyst has a high affinity for water (it absorbs water) and therefore shifts the equilbrium to the right (Le chat's principle). Therefore the catalyst speeds up the chemical reaction
- Esterification is a very slow process: to speed it up
- use a catalyst
- increase the temperature of the system
but in order to increase the temp, you need to reflux it. This is because when you heat the system, volatile products may escape the reaction chamber as a gas. In order to stop this, the gas is condensed using a coolant. This forces the gas into a liquid and therefore no product is lost. This is what refluxing is.
Hope it helps....good luck
- Esterification: is the process of producing an ester by reacting an alkanol and an alkanoic acid in the presence of a sulfuric acid catalyst.
Generally:
Alkanol + alkanoic acid ---------> ester + water
the sulfuric acid catalyst has a high affinity for water (it absorbs water) and therefore shifts the equilbrium to the right (Le chat's principle). Therefore the catalyst speeds up the chemical reaction
- Esterification is a very slow process: to speed it up
- use a catalyst
- increase the temperature of the system
but in order to increase the temp, you need to reflux it. This is because when you heat the system, volatile products may escape the reaction chamber as a gas. In order to stop this, the gas is condensed using a coolant. This forces the gas into a liquid and therefore no product is lost. This is what refluxing is.
Hope it helps....good luck
Also make sure that you can name the ester produced and know its structure.
The ester produced is by reacting the alkanol and alkanoic acid. To name the ester, just get the alkyl group of the alkanol. Then followed by the alkyl group of the alkanoic acid, and" oate"
e.g. ethanol + propanoic acid =======> ethyl propanoate + water
e.g. butanol + ethanoic acid =======> butyl ehanoate + water
The ester produced is by reacting the alkanol and alkanoic acid. To name the ester, just get the alkyl group of the alkanol. Then followed by the alkyl group of the alkanoic acid, and" oate"
e.g. ethanol + propanoic acid =======> ethyl propanoate + water
e.g. butanol + ethanoic acid =======> butyl ehanoate + water
