Problem: A mysterious white powder could be powdered sugar (C12H22O11), cocaine (C17H21NO4), codeine (C18H21NO3), norfenefrine (C8H11NO2), or fructose (C6H12O6). When 82 mg of the powder is dissolved in 1.50 mL of ethanol (d = 0.789 g/cm3, normal freezing point −114.6 oC, Kf = 1.99 oC/m), the freezing point is lowered to −115.5 oC. What is the identity of the white powder?

🤓 Based on our data, we think this question is relevant for Professor Blaha's class at Columbus State Community College.

FREE Expert Solution

(1) Calculate the weight of ethanol

mass of etOH =(1.5 mL)(1 cm31 mL)(0.789 gcm3)(1x10-3 kg1 g)

mass etOH = 1.1835x10-3 kg

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Problem Details

A mysterious white powder could be powdered sugar (C12H22O11), cocaine (C17H21NO4), codeine (C18H21NO3), norfenefrine (C8H11NO2), or fructose (C6H12O6). When 82 mg of the powder is dissolved in 1.50 mL of ethanol (d = 0.789 g/cm3, normal freezing point −114.6 oC, Kf = 1.99 oC/m), the freezing point is lowered to −115.5 oC. What is the identity of the white powder?

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What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Freezing Point Depression concept. If you need more Freezing Point Depression practice, you can also practice Freezing Point Depression practice problems.

What professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor Blaha's class at Columbus State Community College.