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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: Lols123 on June 09, 2011, 07:59:33 am

Title: Quick Question regarding Aspirin
Post by: Lols123 on June 09, 2011, 07:59:33 am
When a questions asks to write an equation for the reaction between aspirin and water, how do we differentiate between the ionizing reaction that happens since its a weak acid and the hydrolysis reaction to form salycilic acid and ethanoic acid?
Title: Re: Quick Question regarding Aspirin
Post by: luken93 on June 09, 2011, 08:36:19 am
If it is a hydrolysis reaction, it's the splitting up into salicylic and ethanoic acid/anhydride, however they'd have to be specific in the question/context to ask you what to do. I doubt they' ever bother asking about how it reacts as a weak acid, there's no point to it haha
Title: Re: Quick Question regarding Aspirin
Post by: Lols123 on June 09, 2011, 08:44:13 am
funnily enough the answer was the reaction as a weak acid :P
but yeah i guess if they dont specify that there are basic conditions, it wouldnt be a hydrolysis

Edit: would you also be able to help me with this one ><
2Ca3(PO4)2 + 6SiO2 + 10C ----> P4 + 6CaSiO3 + 10CO
Theoretically for every mole of reactant, how many moles of P4 are produced?
Title: Re: Quick Question regarding Aspirin
Post by: luken93 on June 09, 2011, 08:52:08 am
Haha that's strange, but I'd say with VCAA they'd say something like "Write a balanced equation for the hydrolysis of Aspirin..."
Title: Re: Quick Question regarding Aspirin
Post by: ulbasour on June 10, 2011, 05:13:57 pm
funnily enough the answer was the reaction as a weak acid :P
but yeah i guess if they dont specify that there are basic conditions, it wouldnt be a hydrolysis

Edit: would you also be able to help me with this one ><
2Ca3(PO4)2 + 6SiO2 + 10C ----> P4 + 6CaSiO3 + 10CO
Theoretically for every mole of reactant, how many moles of P4 are produced?


This is an engage qusn im pretty sure..

First need to suss the limiting reagent, which we can see will be C, as we are using a max amount of 1 mol for each reagent.
Therefore:

2Ca3(PO4)2 : 6SiO2 : 10C

Divide by 10 to achieve 1 mole for the limiting reactant

2/10  :  6/10  : 10/10

.2 : .6 : 1

Its a 10:1 mol ratio between C and P4
Therefore n(P4)= 1/10 = .1 mol