White substance from Dust off ???

[stevenguo360]

I was dusting out my laptop with some Falcon Dust off compressed gas, and to my horror, this white substance came out. I did not have the can upside down or tilted, it was in the upright position. The white substance dissipated quickly though. What is it, and should I be worried? I was dusting my keyboard, with the caps still on. Thanks for the help!

 

[CountMike]

The "white substance" is likely ice !!! When gas is decompressed from liquid it takes energy from air and it condenses, as soon as temps are equalized with environment, it evaporates (sublimation). Just your everyday physics thought in grade school. Lol.