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The instrument used for computing the specific rotation caused by polarized light is called a polarimeter. Once the measurement is acquired, it is substituted in the specific rotation formula.

This helps in finding the specific rotation value, which is a property of a particular compound.

Let A denote the fraction of D-glucose in the $\mathrm{Î\pm }$form and B denote the fraction of D-glucose in the $\mathrm{β}$form.

$\begin{array}{c}\mathrm{A}+\mathrm{B}=1\\ \mathrm{B}=1−\mathrm{A}\end{array}$

The specific rotation of A is 150.7.

The specific rotation of B is 52.8.

The specific rotation of the equilibrium mixture is 80.2.

The specific rotation of the mixture can be found as:

$\begin{array}{c}\text{³§±è±ð³¦¾±´Ú¾±³¦°ù´Ç³Ù²¹³Ù¾±´Ç²Ô´Ç´Ú³Ù³ó±ð³¾¾±³æ³Ù³Ü°ù±ð=³§±è±ð³¦¾±´Ú¾±³¦°ù´Ç³Ù²¹³Ù¾±´Ç²Ô´Ç´Ú´¡Ã—´Ú°ù²¹³¦³Ù¾±´Ç²Ô´Ç´Ú¶Ù-²µ±ô³Ü³¦´Ç²õ±ð¾±²Ô³Ù³ó±ðα´Ú´Ç°ù³¾+}\\ \text{³§±è±ð³¦¾±´Ú¾±³¦°ù´Ç³Ù²¹³Ù¾±´Ç²Ô´Ç´Úµþ×´Ú°ù²¹³¦³Ù¾±´Ç²Ô´Ç´Ú¶Ù-²µ±ô³Ü³¦´Ç²õ±ð¾±²Ô³Ù³ó±ðβ´Ú´Ç°ù³¾}\\ \text{80.2=150.7A+}(1−A)52.8\\ 80.2=150.7A+52.8−52.8A\\ 27.4=203.5A\end{array}$

The value of A can be found as:

$\begin{array}{c}\mathrm{A}=\frac{27.4}{203.5}\\ =0.135\end{array}$

The value of B can be found as:

$\begin{array}{c}B=1−A\\ =1−0.135\\ =0.765\end{array}$

This calculation indicates that 13.5% is in the data-custom-editor="chemistry" $\mathrm{Î\pm }$-D galactose and 76.5% is in the data-custom-editor="chemistry" $\mathrm{β}$-D galactose.