Unlike the medical or clinical thermometer which is used solely to measure human body temperature, a laboratory thermometer has different uses.
A laboratory thermometer is used to measure the boiling point and freezing point during science experiments. It is also used to measure the temperature of substances. It measures temperature ranging between -10 degree Celsius and 110 degree Celsius.
Let’s take a look at different types of laboratory thermometers:
Most thermometers usually fall in the category of science laboratory glassware as it made of glass. The laboratory thermometer can be easily identified through its long stem with a silver bulb at its bottom. The silver colour is nothing but mercury which expands as the temperature goes up and contracts as temperature go down.
Some liquid-in-glass thermometers also contain red alcohol. So, they are also called alcohol or spirit thermometers. However, the liquid content in these thermometers evaporates quickly.
This type of thermometer comprises a lens that focuses the infrared energy (IR) on to a detector. This detector in turn coverts IR into an electric signal that is further displayed in units of temperature. Its application is best suited for taking temperatures from a distance or measuring it from the surface.
The bimetallic strip thermometer is made of two metals bonded together. It is mainly used to control temperatures and hence, finds a wide application in industries. It is ideal for accurate calculation of high-temperature substances or objects. Basically, it converts temperature into mechanical displacement.
When the temperature rises, the strip bends towards the metal which has a low temperature coefficient. On the contrary, when the temperature goes down, the strip bends towards the metal which has a high temperature coefficient.
This thermometer is basically an electronic device. Its name is a blend of thermal and resistor. Its resistance is dependent on temperature. It mainly measures changes in electrical resistance and converts them to changes in temperature.
All these thermometers show display either in Fahrenheit (F) or Celsius (C). They can be used in various applications, depending on types of laboratory experiments.