What color flame is produced by dust particles during combustion?

The flame produced by dust particles during combustion is typically orange. This occurs because the dust particles, when heated, can vaporize and emit light in the visible spectrum, appearing as an orange hue. This phenomenon is observed in various combustion processes where particulate matter is present, leading to incomplete combustion or mixing with the gases produced.

In contrast, a blue flame generally indicates complete combustion where there is a sufficient mix of fuel and oxygen, which doesn't result in the visible emissions one might see with dust particles or other particulates. White flames are often associated with high-temperature combustion, but they do not represent the presence of dust. Yellow flames can be indicative of the presence of sodium or other materials that vaporize at lower temperatures, but they do not specifically represent dust particles. Hence, the characteristic orange flame is directly connected to the combustion of dust particles.