Question

the dissociation of constant benzoid acid is 6.6x×10-5 calculate the hydrozen ions in concentration of a solution containing 1.22 g of benzoic acid 2000 ml of water​

Answer 1

Explanation:

Let s M be the solubility of silver benzoate in water.

[Ag+]=[PhCOO−]=sM

Ksp=[PhCOO−][Ag+]=s×s=s2=2.5×10−13

s=5.0×10−7M. This is solubility of silver benzoate in pure water.

pH=−log[H+]=3.19

[H+]=6.456×10−4

Benzoate ions combine with protons to form benzoic acid but hydrogen ion concentration is constant due to buffer solution.

PhCOOH⇌PhCOO−+H+     

Ka=[PhCOOH][PhCOO−][H+]

[PhCOO−][PhCOOH]=Ka[H+]=6.46×10−56.456×10−4=10

Let y M be the soubiity in the buffer solution.

y=[Ag+]=[PhCOO