A. The specific rotation, [] D , for (-)-malic acid is - 27 . What is the observ

Question

A. The specific rotation, []D, for (-)-malic acid is -27. What is the observed rotation for a solution of 1.5 g of (-)-malic acid in 10 mL of water in a sample tube having a pathlength of 10 cm?

B. The observed rotation of a solution of 0.92 g of a compound in 10 mL of water is +3.7 degrees. If the pathlength is 10 cm, what is the specific rotation of the compound?

C. The specific rotation, []D, for (-)-malic acid is -27. What is the observed rotation for a solution of 1.2 g of (-)-malic acid in 10 mL of water in a sample tube having a pathlength of 10 cm?

D. The observed rotation of a solution of 1.2 g of a compound in 10 mL of water is +1.3 degrees. If the pathlength is 10 cm, what is the specific rotation of the compound?

Explanation / Answer

A.)

specific rotation = - 27

concentration = 1.5 / 10 = 0.15 g/mL

path length = 10 cm

specific rotation = observed rotation / concentration x length

- 27 = observed rotation / 0.15 x 1

observed rotation = - 4.05

B.)

cocentration = 0.92 / 10 = 0.092 g/mL

specific rotation = 3.7 / 0.092 x 1

specific rotation    = 40.2

C)

- 27 = observed rotation / 0.12 x 1

observed rotation = - 3.24

D).

specific rotation = 10.8

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.