Which statement is true regarding air temperature and density?

The correct statement is that hot air rises above cold air. This occurs due to the differences in density caused by temperature variations. When air is heated, the molecules move more rapidly and spread apart, resulting in a lower density compared to colder air. Consequently, since colder air is denser, it tends to sink, causing the warmer, less dense air to rise above it. This principle is fundamental in meteorology and explains many atmospheric phenomena, including weather patterns and convection currents.

In contrast, the idea that hot air is denser than cold air is inaccurate because hot air, having less density, cannot sink. The notion that cold air rises above hot air contradicts the basic behavior of gases in relation to temperature. Lastly, the statement about all air being uniformly dense does not hold true, as air density varies significantly with temperature, pressure, and humidity. Understanding these principles is crucial for anyone studying atmospheric science or related fields.