you titrated an unknown acid with 0.0925 M NaOH, 0.6201g of the unknown acid was placed...

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you titrated an unknown acid with 0.0925 M NaOH, 0.6201g of the unknown acid was placed...

you titrated an unknown acid with 0.0925 M NaOH, 0.6201g of the unknown acid was placed into an Erlenmeyer flask with10 ml of water and 2-3 drops of phenolphthalein. It took 32.34ml of NaOH to reach the endpoint. What is the molecular weight and the pKa of the unknown acid?

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Answer 1

Answer #1

NaOH + HA ----------> NaA + H2O

moles of NaOH consumed = 0.0925 x 32.34 / 10000 = 0.0030

0.0030 moles acid consumed

moles = mass / molar mass

molar mass= mass / moles = 0.6201 / 0.0030

molar mass = 206.7 g.mol

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Answer 2

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