refractometer.pptx

Working, Principle and applications of Refractometer

1. An Overview on Refractometer Prepared by Anil Sharma , Sr. Executive, Compliance, USV Private Limited 1 of 12

2. When a ray of light passes from one medium to another it suffer refraction. 2 of 12

3. What is a Refractometer? A  refractometer  is a simple instrument used for measuring concentrations of aqueous solutions. It requires only a few drops of liquid, and is used throughout the  food ,  agricultural ,  chemical , and manufacturing industries. What is Refractive Index? Refractive Index n is the speed of light in vacuum relative to the speed of light in the considered medium: n = speed of light in vacuum / speed of light in medium n = c/v n = Refractive index. c = Speed of light in vacuum. v = Velocity of light in Medium. Example: Water has a refractive index of 1.33 which means that the light travels 1.33 faster in vacuum than in water. The refractive index is a physical property of the liquid. 3 of 12

4. 4 of 12 Snell’s law Snell's law states that the ratio of the  sines  of the angles of incidence and refraction is equivalent to the ratio of  phase velocities  in the two media, or equivalent to the reciprocal of the ratio of the  indices of refraction : θ 1 is the angle of Incidence. θ 2 is the angle of Refraction. V 1 is the velocity of light in the Air. V 2 is the velocity of light in the Medium. N 1 Refractive index if Air. N 2 Refractive index if Medium.

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6. How a Refractometer Works When light enters a liquid it changes direction; this is called refraction.  Refractometers measure the degree to which the light changes direction, called the angle of refraction. A refractometer takes the refraction angles and correlates them to refractive index (nD) values that have been established. Using these values, you can determine the concentrations of solutions. For example, solutions have different refractive indexes depending on their concentration in water. 6 of 12

7. Refraction of light into New Medium: Light changing speed in a new medium creates a bending. If light is traveling slower in the new medium i.e. from less dense to more dense medium like from air to water, it will bend towards the normal line. so that angle of the refraction is less than angle of incidence. If light is traveling faster in the new medium i.e. from more dense to less dense medium like from water to air, it will bend away from the normal line. so that angle of the refraction is more than angle of incidence. 7 of 12

8. 8 of 12 Influence of temperature and wavelength The refractive index depends on the temperature of the media: The higher the temperature of a media that means the liquid becomes less dense and less viscous, causing light to travel faster in the medium. Thus higher the speed of light in the media and the lower its refractive index. In vacuum light travels at a constant speed (c), independent of its wavelength. In all other media, however, the speed of light depends as well on its wavelength: The shorter the wavelength of the light, the higher its speed. The refractive index has thus always to be stated together with the wavelength of the light used for the measurement and the temperature of the media. Its important to use monochromatic lights to prevent dispersion of light into different colours. The refractive index is normally measured at a temperature of 20°C using light with the wavelength of the sodium D line (589.29 nm) and is therefore expressed as nD20.

9. 9 of 12 Degrees Brix  (symbol ° Bx ) is the  sugar  content of an aqueous solution. One degree Brix is 1 gram of  sucrose  in 100 grams of solution and represents the strength of the solution as  percentage by mass . The higher the temperature of a media that means the liquid becomes less dense and less viscous, causing light to travel faster in the medium. Thus higher the speed of light in the media and the lower its refractive index.

10. 10 of 12 Uses of Refractive index It can be used to characterized liquid and solid samples. Measure the concentration of solutions e.g. sugar content in alcohol. It can use to check sample for purity. RI can be used for qualitative & quantitative analysis as well as structural analysis. The refractive index of a substance is dependant on the wavelength λ of the light and the temperature T of the substance.

11. 11 of 12 CSV of Refractometer URS (J-QC-URS-RFM-01) Business Requirements Interface Requirements Security and safety Requirements Electronic Records, Reports and Electronic Signature Requirements Audit Trail Requirements Backup, Archival and Restoration Requirements HLRA (J-QC-HLRA-RFM-01)

12. 12 of 12 CSV of Refractometer IQ (J-QC-IQ-RFM-01) Verification of pre-requisite Physical Identification Verification of system hardware Identification of software version Environmental Condition Verification Verification of Software Backup Verification of system startup and shutdown Verification of Application installation of Directory Date & Time Synchronization Verification OPQ (J-QC-OPQ-RFM-01) Verification of Draft/Approved SOP IQ protocol Completion Verification Training Verification, Physical and Logical Security Verification User Management Verification, Password Policy Verification Verification of Access Control, Verification of Communication Failure