liquid nitrogen
Magnetic resonance imaging NMR devices use liquid nitrogen to cool the superconducting magnets. Nitrogen is a gas at room temperature and liquefies at -195.8C. Its neighbor on the periodic table oxygen boils at -182.95C. The interactions between nitrogen molecules N 2 are weaker, so the boiling point is lower. Interactions between non-polar molecules depend on the degree of electron fluctuation within the molecule.