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ersity-CEM 103 × id-4826943 ning Jump to.. Khang Huynh core s/6/2018 1159 PM 3 9

ID: 1026284 • Letter: E

Question

ersity-CEM 103 × id-4826943 ning Jump to.. Khang Huynh core s/6/2018 1159 PM 3 94/100o Mapd A Sapling Learning The fask shown here concains 0 821 g of acid and a few drops of phe 25 in water. The buret contains 0.150 M NaOH. 15 What volume of base is needed to reach the end point of the Stration? 35 mL. base What is th is dip of the acid (assuming it the second equivalence point)? Add base to the solution unti it just turns pink. You may need to reset the btration if you go past the end point Number g/mol about us careers privacy pelicyterms of contact us help MacBook Air

Explanation / Answer

a)

from the diagram :

volume of base needed = 30.5 mL

b)

mmoles of NaOH = mmoles of acid

moles of NaOH = 30.5 x 0.150 / 1000

                         = 4.575 x 10^-3 mol

moles of acid = mass / molar mass

4.575 x 10^-3 = 0.821 / molar mass

molar mass = 179 g/mol