Science has progressed considerably with time. There are various devices that are being used for various scientific experiments. One such device is refractometer. And like every other mechanical device, it has some errors in its readings too. Let’s evaluate certain facts relating to a digital refractometer.For those who are not very clear regarding the idea of this device:
What is a digital refractometer?
A digital refractometer is a scientific device used in a lab to measure the refractive index of a liquid.
A digital refractometer works on the principle of light refraction defined by Snell’s Law and measures the critical angle that is formed on a refractive surface.
What are the possible errors that might occur in a digital refractometer?
There are two basic sources of error as far as the reading of a refractometer is concerned. They are:
- Temperature: the temperature of the surrounding, the refractometer, and the liquid may vary from each other which leads to the considerable amount of deflection of the reading of the device. The deflection of the reading for per degree of temperature varies for each different liquid and the different concentration of the same liquid.
- Evaporation: evaporation is another factor that affects the reading of a refractometer. This depends on three factors, the temperature, and density of the selected device and the surface area of the container of the liquid. The higher the temperature, the lower the density of the liquid and the larger the surface area, the greater the evaporation.
How to get rid of these errors?
As already mentioned, there are two sources of error. So if those two factors are brought under control, one could easily get an accurate measure. Let’s see how they can be maintained at a steady level:
- Controlling Temperature: there are three temperatures in total that need to be taken care of. The temperature of the refractometer, the liquid, and the ambient temperature. If all these three are brought into an equilibrium, the reading gets more or less accurate. The time they require to reach an equilibrium is directly proportional to the viscosity of the liquid. The denser the liquid is, the longer it will take to come into equilibrium.
- Limiting Evaporation: evaporation cannot be stopped and it only concerns the liquid that is being used. If the temperature of the liquid can be controlled, then the evaporation can be regulated. As evaporation takes place from the surface of the liquid, containers with smaller circumference are recommended for this experiment. Though there is a particular type of digital refractometer that inhibits the air flow with an evaporation cover and limits the volume and as a result, the evaporation is reduced.
Traditional refractometers or manual ones increase the effort as well as the chance of a deflected reading while the digital ones are automated and take care of the possible errors to a great extent. These are easily available in various online stores. So, one can easily get their hand on the preferred refractometer.
