A chemistry graduate student is given 100. mL of a 0.90M hydrocyanic acid (HCN) solution. Hydrocyanic acid is a weak acid with K, =4.9 x 10 . What mass of KCN should the student dissolve in the HCN solution to turn it into a buffer with pH =8.97? You may assume that the volume of the solution doesn't change when the KCN is dissolved in it. Be sure your answer has a unit symbol, and round it to 2 significant digits.

A chemistry graduate student is given 100. mL of a 0.90M hydrocyanic acid (HCN) solution. Hydrocyanic acid is a weak acid with K, =4.9 x 10 . What mass of KCN should the student dissolve in the HCN solution to turn it into a buffer with pH =8.97? You may assume that the volume of the solution doesn't change when the KCN is dissolved in it. Be sure your answer has a unit symbol, and round it to 2 significant digits.

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter15: Additional Aqueous Equilibria

Section: Chapter Questions

Problem 93QRT: When 40.00 mL of a weak monoprotic acid solution is titrated with 0.100-M NaOH, the equivalence...

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