Answer:
At the second equivalent point 200 mL of NaOH is required.
Explanation:
at the first equivalent point:
H2A + OH- = HA- + H2O
initial mmoles y*100 y*100 - -
final mmoles 0 0 y*100 y*100
at the second equivalent point:
HA- + OH- = A2- + H2O
initial mmoles y*100 y*100 - -
final mmoles - - y*100 y*100
at the second equivalent point we have that y*100 mmoles of NaOH or 100 mL of NaOH ir required, thus:
at the second equivalent point 200 mL of NaOH is required.
H2O is the missing reactant.
Just a caveat: this equation isn’t balanced.
Answer:
A buffer solution is a mixture of two pair salts to maintain a stable pH.
Explanation:
This mixture is made always with a complementary pair of salts (one acid an another basic).
Example:
Acetic Acid (CH3COOH) and Sodium Acetate (NaH3COO).
So when you add a little bit more acid to this mixture, the basic part of the buffer, in this case the Sodium Acetate, will neutralize it and the pH will remain the same.
On the other hand, if the mixture receives some basic substance, the acid part of the buffer, the acetic acid, will neutralize it, so again the pH will remain the same.
Answer:
Yield of reaction is 76.7%
Explanation:
The reaction of salicylic acid with acetic anhydride to produce acetyl salicylic acid is 1:1. That means 1 mole of salicylic acid reacts with 1 mole of acetic anhydride (Acid is catalyst of reaction).
Moles of salicylic acid are:
And moles of acetic anhydride are:
As salicylic acid is limiting reactant, theoretical moles of acetyl salicylic acid are 0.04127mol. That means theoretical mass of acetyl salicylic acid is:
Thus, yield of reaction is:
<em>76.7%</em>
