Ethanol-filled thermometers are used in preference to Mercury for meteorological measurements of minimum temperatures and can be used down to −70 °C (-94 °F). The physical limitation of the ability of a thermometer to measure low temperature is the freezing point of the liquid used.
Alcohol
Water - Galileo Galilei invented a rudimentary water thermometer in 1593 which, for the first time, allowed temperature variations to be measured
The red liquid in a liquid-in-glass thermometer is mineral spirits or ethanol alcohol mixed with red dye. A grey or silver liquid inside the thermometer is mercury. Mercury thermometers are not used anymore due to the dangers associated with mercury.
When a thermometer is exposed to warmth, the liquid inside it expands and rises up the tube. This is because heat causes the molecules in the liquid to move faster, taking up more space and causing the volume to increase. The expansion of the liquid is used to measure the temperature.
Because that will mess with the temperature reading on the thermometer. And it would be dangerous if the thermometer is broken as there are dangerous chemicals (i.e.mercury) inside.
The two substances used in a liquid column thermometer are mercury and alcohol. Mercury thermometers use mercury as the liquid inside the glass tube, while alcohol thermometers use colored alcohol such as ethanol or dyed ethanol.
The liquid typically used in a Galilean thermometer is colored alcohol.
We still use colored alcohol for our liquid in everyday thermometers.
A thermometer is used to measure air temperature, or the temperature within a solid or liquid.
iodine and Mercury
Mercury
Liquid is used in a thermometer because it expands and contracts uniformly with changes in temperature, allowing for accurate temperature measurements. The liquid inside the thermometer expands and rises in the capillary tube as it gets warmer, providing a visible indication of temperature.
A thermometer is most commonly used to measure the temperature of a liquid. Other methods, such as infrared thermometers or thermocouples, can also be used depending on the specific application and characteristics of the liquid.
A laboratory thermometer is used to check the temperature, or changes in temperature, of an object with precise accuracy.
The liquid in a thermometer does not move when turned upside down because of the properties of the liquid used (usually mercury or alcohol) and the vacuum-sealed tube design of the thermometer. This design prevents the liquid from freely moving when the thermometer is inverted.
The liquid is an antiseptic used to sterilise it. You wouldn't want to be contaminated with any bacteria or viruses from the last person who used the thermometer, would you?
The keyword "what" in a Galileo thermometer is used to indicate the temperature at which the liquid-filled bulbs inside the thermometer are floating.
When the liquid in a thermometer contracts, it means that the temperature is decreasing. As the molecules of the liquid lose energy, they move closer together, causing the volume of the liquid to decrease. This contraction is used to measure a drop in temperature on the thermometer scale.