Answer:
pH = 3.37
Explanation:
A weak acid as lactic acid in a solution with sodium lactate (Its conjugate base) produce a buffer. The pH of this buffer is obtained using H-H equation:
pH = pKa + log [A-] / [HA]
<em>Where pH is the pH of the buffer,</em>
<em>pKa is 3.86</em>
<em>And [] could be taken as the moles of A- = Sodium lactate and HA = Lactic acid.</em>
<em />
Moles A-:
40.0mL = 0.0400L * (0.75mol / L) = 0.030 moles A-
Moles HA:
75.0mL = 0.0750L * (1.25mol / L) = 0.09375 moles HA
Replacing:
pH = 3.86+ log [0.030 moles A-] / [0.09375 moles HA]
<h3>pH = 3.37</h3>
<em />
The answer should be "Dunes"
CH3CH2OH = 46.068 (molar mass)
1.50g(1 mole / 46.0680) =
0.03256 moles
