1 The largest school district by enrollment with an election in 2016 is Wake County Public School System with 153,534 K-12 students.  The smallest North Carolina school district among the nation's largest with an election in 2016 is Duplin County Schools with 9,628 K-12 students.
Freon only remains a liquid while under pressure inside your refrigerator's cooling system. The chemical changes to a gas as soon as it contacts the air. This means, when you smell freon in and around your refrigerator, you're also inhaling varying amounts of freon gas. According to the Environmental Protection Agency, freon gas is denser than air and travels very slowly to the upper atmosphere.
Density of Nitrogen and Air   If you are asking whether nitrogen is less dense than air and will float on top of it, then yes, nitrogen is lighter, albeit only slightly â¦ . More accurately, nitrogen, which is a constituent gas of air, is less dense than air, not lighter.   The density of air at standard temperature and pressure is 1.292 kg/m3. The density of nitrogen is 1.251 kg/m3.