need help on acid and base multiple choice question Watch

Stormragexox
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Hey guys I am completely stuck can someone guide me through this question please
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Stormragexox
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(Original post by Stormragexox)
Hey guys I am completely stuck can someone guide me through this question
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Kian Stevens
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Slightly higher.
Solution F is the start of a slow esterification reaction. Solution G is the equilibrium formed due to the reaction.
The equilibrium will be: propanoic acid + methanol \rightleftharpoons methyl propanoate + water.

In Solution F, some of the propanoic acid will dissociate into H3O+, to give a pH.
The concentration of propanoic acid will decrease as the reaction proceeds, gradually resulting in the equilibrium being formed in Solution G.
However, since there's already an excess of water from Solution F, the equilibrium formed will be well towards the left hand side, favouring the production of propanoic acid (and methanol). However, the propanoic acid will be of a smaller concentration than in Solution F, as some has reacted to form products.
So, the propanoic acid that's left will be disassociating. But, a smaller concentration of propanoic acid means a smaller concentration of H3O+, which by definition results in a higher pH.
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Stormragexox
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(Original post by Kian Stevens)
Slightly higher.
Solution F is the start of a slow esterification reaction. Solution G is the equilibrium formed due to the reaction.
The equilibrium will be: propanoic acid + methanol \rightleftharpoons methyl propanoate + water.

In Solution F, some of the propanoic acid will dissociate into H3O+, to give a pH.
The concentration of propanoic acid will decrease as the reaction proceeds, gradually resulting in the equilibrium being formed in Solution G.
However, since there's already an excess of water from Solution F, the equilibrium formed will be well towards the left hand side, favouring the production of propanoic acid (and methanol). However, the propanoic acid will be of a smaller concentration than in Solution F, as some has reacted to form products.
So, the propanoic acid that's left will be disassociating. But, a smaller concentration of propanoic acid means a smaller concentration of H3O+, which by definition results in a higher pH.
Thank you for replying what would react with the propanoic acid to decrease its concentration
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Kian Stevens
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(Original post by Stormragexox)
Thank you for replying what would react with the propanoic acid to decrease its concentration
The methanol.
Like I mentioned in my initial reply, this is an esterification reaction. Hence, the propanoic acid will react with the methanol to produce methyl propanoate.
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