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qid 3659 · chemistry

Question: The concentration of cholesterol dissolved in chloroform is 6.15 g per 100 ml of solution. (a) A portion of this solution in a 5-cmpolarimetertube causes an observed rotation of -1.2°. Calculate the specific rotation of cholesterol. (b) Predict the observed rotation if the same solution were placed in a 10-cm tube. (c) Predict the observed rotation if 10 ml of the solution were diluted to 20 ml and placed in a 5-cm tube.

  1. -39.0, -2.4, -0.6
  2. -41.0, -2.2, -0.4
  3. -42.0, -2.1, -0.3
  4. -37.0, -2.6, -0.8
  5. -38.5, -2.35, -0.65
  6. -38.0, -2.3, -0.6
  7. -40.5, -2.45, -0.55
  8. -40.0, -2.4, -0.5
  9. -39.0, -2.5, -0.7
  10. -36.0, -2.7, -0.9

Our answer: A. -39.0, -2.4, -0.6 Source quote machine-checked (exact quote)

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Current source

Wikipedia, "Specific rotation"

https://en.wikipedia.org/wiki/Specific_rotation

“It is defined as the change in orientation of monochromatic plane-polarized light, per unit distance–concentration product, as the light passes through a sample of a compound in solution.”

Source quote machine-checked (exact quote)

retrieved 2026-09-18T01:08:19.522Z

page text sha256 21710b94befeeeba… · content sha256 120286a72114f7a2…

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Earlier version (superseded)

https://en.wikipedia.org/wiki/Specific_rotation

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addendum formula_qid3659.formula_ADDENDUM_source_bf20260917T014332Z · sha256 c2788821b30e9c39… · replaces the version below, addendum sha256 28d1464305fbd44f…

Earlier version (superseded)

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