Answer to Question #325675 in General Chemistry for Raphael

Question

2. A 0.2719 g sample containing 𝐶𝑎𝐶𝑂3 reacted with 20.00 mL of 0.2254 M HCl. Given that HCl was excess. The excess HCl required exactly 20.00 mL of 0.1041 M NaOH to reach the end-point using phenolphthalein indicator.

Determine percentage purity of 𝐶𝑎𝐶𝑂3 in the sample. The reaction involved is

𝐶𝑎𝐶𝑂3(𝑠) + 2𝐻𝐶𝐼(𝑎𝑞) → 𝐶𝑎𝐶𝐼2(𝑎𝑞) + 2𝐻2O(l)

The titration reaction is

𝐻𝐶(𝑎𝑞) + NaOH(aq) 𝑁𝑎Cl(𝑎𝑞) + 𝐻2𝑂(l)

Answer 1

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