what about a mixture whose specific rotation was found to be -9.2 degree?
The specific rotation is a property of a substance that measures the angle of rotation exhibited by plane-polarized light as it passes through a sample. The specific rotation value is typically reported with a unit symbol, such as degrees per decimeter (°/dm) or degrees per g/mL (°/g/mL).
In your question, the specific rotation of a mixture is given as -9.2 degrees. However, to fully understand the composition of the mixture, we need some additional information. The specific rotation of a mixture is influenced by both the concentration and specific rotation values of its individual components. Without knowing these factors, it is not possible to determine the composition of the mixture.
To find out more about the mixture and determine its components, you could employ a method called polarimetry. Here are the steps to follow:
1. Set up a polarimeter: A polarimeter is a device used to measure the rotation of polarized light. It consists of a light source, polarizer, sample cell, analyzer, and detector.
2. Calibrate the polarimeter: Before analyzing the mixture, it's essential to calibrate the polarimeter using a known standard. This process ensures accurate measurements by accounting for any instrument biases or variations.
3. Measure the rotation of the mixture: Place the mixture in the sample cell of the polarimeter. The source emits polarized light, which passes through the polarizer, sample cell, and analyzer. The analyzer detects the intensity of transmitted light and measures the angle of rotation.
4. Compare the measured rotation: Use the specific rotation values of known substances to compare with the measured rotation of the mixture. This step requires a database or reference material containing specific rotation values of various substances.
5. Analyze the results: By comparing the measured rotation with the known specific rotations, you can determine the likely composition of the mixture. This process involves analyzing the observed rotation, considering concentration, and using mathematical equations like the specific rotation equation to calculate the composition accurately.
It's worth noting that identification of individual components in a mixture via polarimetry can be challenging, especially in complex mixtures where multiple substances may contribute to the observed rotation. Therefore, employing additional analytical techniques, such as chromatography or spectroscopy, may be necessary to confirm the composition and identify the specific substances present.