Ask me for chemistry help! (5 Viewers)

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Dylanamali

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MagnificentOne said:
What is Le chatelier's principle?
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Applies to reversible reactions - states that if a system at equilibrium is disturbed, the system will shift in order to minimise the disturbane and obtain a new point of equilibrium.
 
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Dylanamali

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kittyful said:
Why do we reflux ?
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Refluxing is the process done is esterification. Esterification is naturally a very slow process (the reaction between a alkanol and an alkanoic acid). Because of this we need heat, however both of the reactants are volatile and thus heating under an open system would cause a loss of reactants due to evaporation - however heating in a closed system will cause a build up in pressure, possibly resulting in explosions and the like - because of this we use a process known as refluxing which is basically attaching a condenser which condenses the reactants as they evaporate, minimising the loss of reactants, but still enabling the heating to speed up the reaction. The reaction is also sped up through the use of a conc. sulfuric acid catalyst which acts as both a catalyst as well as a dehydrating agent by absorbing the product of water and thus increasing the yield of the ester.
 
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yew

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Refluxing is done to allow for high temperatures, the reactants may condensate, but will drip back down ??
 
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MagnificentOne

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Dylanamali said:
Refluxing is the process done is esterification. Esterification is naturally a very slow process (the reaction between a alkanol and an alkanoic acid). Because of this we need heat, however both of the reactants are volatile and thus heating under an open system would cause a loss of reactants due to evaporation - however heating in a closed system will cause a build up in pressure, possibly resulting in explosions and the like - because of this we use a process known as refluxing which is basically attaching a condenser which condenses the reactants as they evaporate, minimising the loss of reactants, but still enabling the heating to speed up the reaction. The reaction is also sped up through the use of a conc. sulfuric acid catalyst which acts as both a catalyst as well as a dehydrating agent by absorbing the product of water and thus increasing the yield of the ester.
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Splended!
 
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