A Chemist Is Given a White Solid That Is Suspected

question 65

Essay

A chemist is given a white solid that is suspected of being pure cocaine (molar mass = 303.35 g/mol). When 1.22 g of the solid is dissolved in 15.60 g of benzene, the freezing point is lowered by 1.32°C. The molar mass is calculated from these data to be 303g. Assuming the following uncertainties, can the chemist be sure the substance is not codeine (molar mass 299.36)? K_f for benzene is 5.12°C/m.Uncertainties
Mass of solid = ±0.01 g
Mass of benzene = ±0.01 g
ΔT (freezing-point lowering) = ±0.04°C
K_f = ±0.01
Support your answer with calculations.

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Definitions:

Violent Outbursts

Sudden and intense expressions of violence, often uncontrolled and aggressive.

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Refers to having a broad scope of judgment or choice available.

Professionalism

The conduct, aims, or qualities that characterize or mark a profession or professional person; often involving competence, skill, and adherence to ethical standards.

Accountability

The obligation of individuals or organizations to account for their activities, accept responsibility for them, and disclose the results in a transparent manner.