The instrument commonly found in laboratories with a hot blue flame is a Bunsen burner. A Bunsen burner produces a steady and controlled flame when a stream of flammable gas (usually natural gas, butane, or propane) is mixed with air before ignition. It is widely used for heating purposes.

Bunsen burners consist of a brass tube connected to a gas source. At the base of the tube, there is an air intake hole that allows the adjustment of the gas-to-air ratio. When the gas and air mixture ignites, the blue flame is generated at the top of the tube. By regulating the air intake, the temperature and size of the flame can be controlled.

The intense heat of the Bunsen burner's blue flame makes it suitable for diverses laboratory applications, including:

1. Heating chemicals in test tubes or crucibles,

2. Sterilizing equipment,

3. Soldering or welding,

4. Melting substances,

5. Combustion reactions,

6. Glassblowing or working with glass tubing,

7. Evaporation,

8. Qualitative chemical analysis (flame tests for cations),

9. Igniting and adjusting the flame of other gas burner or equipment's.

Due to its precise and controllable flame, the Bunsen burner remains an essential tool in laboratories, education institutions, and research facilities for conducting various types of experiments and procedures that require heating and accurate temperature adjustments.