Question

A tube of length 20 cm containing sugar solution rotates the plane of polarization by 11⁰. If the specific rotation of sugar is 66⁰, the strength of the sugar solution is:
1. 0.0667 g/cc
2. 0.0833 g/cc
3. 0.0400 g/cc
4. 0.0886 g/cc

Answer 1

Correct Answer - Option 2 : 0.0833 g/cc

Concept:

The specific rotation of a solution is given as:

\({S } = \frac{{10θ }}{{lc}}\)

Where,

l is the length of the tube in cm

θ is the rotation of the plane of polarization

c is the strength of the solution

S is the specific rotation of sugar

Calculation:

Given: 

l = 20 cm, S = 66^o, θ = 11^o

\(66^\circ = \frac{{10\times11 }}{{20 \times c}}\)

c = 0.0833 g/cc