28. Liquid Nitrogen boils at A.77 kelvin B.82 Kelvin C.54 kelvin D.97 Kelvin
Answer: Option A Solution: Liquid nitrogen is very cold! At normal atmospheric pressure, nitrogen is a liquid between 63 K and 77.2 K (-346°F and -320.44°F). Over this temperature range, liquid nitrogen looks much like boiling water. Below 63 K, it freezes into solid nitrogen. Because liquid nitrogen in a usual setting is boiling, its usual temperature is 77 K.
