Is ClF3 Polar or Nonpolar?

Answer: ClF3 is a polar molecule due to the presence of two pairs of lone pair electrons. The resulting electron-electron repulsion causes a bent structure, leading to an unequal distribution of charge. This induces a permanent dipole. 

Due to the presence of extremely electronegative fluorines (3.98) the impact of the lone pairs of electrons is dented and therefore the dipole moment is weaker than in a comparable molecule such as ClH3. As a result ClF3 has a melting point of -76˚C and a boiling point of 12˚C. At Standard Temperature and Pressure (as defined by IUPAC - not the definition of the U.S. Imperial System) the molecule is a liquid. Due to the large number of fluorines the molecule is able to form a large amount of other compounds involving fluorine.

ClF3 Ball and Stick Model
ClF3 Ball and Stick Model. Created with MolView.
How is ClF3 utilized in the real world?

Due to large amount of halides within the molecule the substance is extremely poisonous, toxic, reactive and combustible. Since the bonds store a large amount of energy there is little input required to encourage these effects. As a result of handling concerns (since it can spontaneously burn living tissue) ClF3 has a few very specialized uses. It can be utilized in the semiconductor industry to clean chemical vapor deposition chambers since it can remove the metal from the machines without requiring the walls to be replaced. It was also explored for potential military applications and rocket fuel but manufacturing and usage difficulties prevented these from becoming a reality on a large scale.