Question

The acetic acid/acetate buffer system is a common buffer used in the laboratory. Write the equilibrium equation for the acetic acid/acetate buffer system. The formula of acetic acid is CH,CO,H. equilibrium equation: Which way does the equilibrium shift if more H,O is added? The equilibrium will not change. The equilibrium will shift to the left. The equilibrium will shift to the right. Which way does the equilibrium shift if more OH” is added? The equilibrium will shift to the right The equilibrium will shift to the left. The equilibrium will not change.

Answer 1

Acetic Acid and Acctate ions are in equilibrium in Buffer system. T Equilibrium equation al CH₃COOH + H₂O CH₂600 + H₂ot Acetic acid Acetate IF - H₃04 added * Equilibrium will shift to left side & Because in presence of acid (H₂0+) Acetic Acid (CH₂ 2004) will Predominate. It more on (Base) added Equilibrium will Shift to right side at High Of Amount Ionization of Ct₂cool will occur and CH₂000 will predominate 30.5 me of o.ogoom Acctic Acid means = 30.5 x 0.090o = 2.745 milimoles now total volume is 100 me But number of moles present are still same - moles of Acetic acid = 2.745 x 10-3 moles - Imoles of Acetic acid = 0.002745 moles

19.5 me of 0.09oom sodium Acetate means = 19.5x 0.090o = 1.755 milimoles now total volume is 100 me But moles of Sodium Acetate are still same. So. no. of moles of Sodium Actale = 1.7550103 Imoles of sod-Acetate = 0.001755 moles / . Concentration of (430) + = 2.72 x 10m we know the Formula For pH pH = -log [H₃O+] ph= -log (2-72x10-5) pH = -log(0.0000272) 1 pH = 4.56 /
when H3O+ are added equilibrium will shift to left side.

When OH- are added then equilibrium will shift to right side.

No. Of moles of acetic acid is 0.002745 moles

No. Of moles of sodium acetate is 0.001755 moles

pH of the buffer solution is 4.56