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Suppose your laboratory instructor inadvertently gave you a sampleof KHP contami

ID: 75642 • Letter: S

Question

Suppose your laboratory instructor inadvertently gave you a sampleof KHP contaminated with NaCl to standardize your NaOH. How wouldthis affect the molarity you calculated for your NaOH solution?Justify your answer.

Here are two examples, yet completely WRONG answers so DO NOT usethese, "The weight would be more because the KHP contains NaCLcausing the molarity to be less in result". OR "The molarityreading would have been too low because the number of moles of NaOHmeasured would have been too low".

Explanation / Answer

Though NaCl is a nutral salt that would not affect theacid-base reaction (or titration), any impurity in KHP would makeyour calculation of mole of KHP inacurate based on the weight ofwhat you thought as pure KHP. This would make the normalityappeared higher. Second Explantion: NaCl is an inactive compound and will not react with either.Hence, the only way it would affect anything would be throughdilution of the sample of KHP. Hence, the molarity calculated wouldlikely be lower than the actual molarity of NaOH, as more KHP isrequired for titration to reach the endpoint for the NaOH than fora pure sample. Hope this helps~Please Rate! Hope this helps~Please Rate!