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.
Nitrogen gas is less dense than air. Nitrogen is lighter than air because it has a lower density than air. The density of #N_2# gas at STP is #1.2056 kg/m^3#, and the density of air at STP is #1.293 kg/m^3#. So, there is less mass of #N_2# per cubic meter, and a greater mass of air per cubic meter.