In color theory, a purple is defined as any non-spectral color between violet and red (excluding violet and red themselves). The spectral colors violet and indigo are not purples according to color theory but they are purples according to common English usage since they are between red and blue.
Dry ice fog is a thick, dense, low-lying fog created exactly the way fog in nature is. created, by condensing water vapor out of the atmosphere. We use dry ice (the. solid form of carbon dioxide) to condense the water vapor out of the air. Dry ice. fog contains no chemicals, glycols, or oils, and is truly a water based fog.
During the winter months, fog will form when humid air moves over a cold surface. Winter fog is more common around bodies of water and is sometimes called lake effect fog. Freezing fog, or Steam fog tends to occur in localized areas where cool air passes over warm, moist land.