In laboratory practice, what is the main purpose of using hot hands?

The main purpose of using hot hands in laboratory practice is to safeguard hands from heat or cold. Hot hands typically refer to protective heat-resistant gloves or pads that allow individuals to handle hot or cold items safely without the risk of burns or frostbite. This tool is especially important in laboratory settings where one may be working with heated glassware, hot metal, or cold substances like ice or liquid nitrogen.

The other choices, while they may sound related to laboratory practices, do not accurately reflect the primary function of hot hands. Measuring temperature typically involves thermometers or temperature probes, protecting desensitized surfaces can involve other forms of coverings or materials, and mixing solutions usually requires specific apparatus like vortex mixers or magnetic stirrers, rather than gloves or pads. Hence, the primary role of hot hands rests firmly in the protection of the user's hands from extreme temperatures.