The molecule CBr4 is non-polar. This is because the charges from the bromine atoms cancel out, resulting a neutral charge.
The molecule CBr4 is called tetrabromomethane, but is commonly known as carbon bromine. It is a commonly used solvent degreaser, but also has applications in the medical industry as a sedative and in the rubber industry for vulcanization and blowing.
When molecules are polar, they have a net dipole moment. The dipole moment of CBr4 is 0 from the atoms cancelling out. In order to determine the dipole moment, one must consider the geometry of the chemical bond of the atoms. Where each molecule is placed determines if there is a net dipole moment. Because the CBr4 molecule has a tetrahedral shape, with the carbon atom in the middle with four bromine atoms attached to the sides, the net charges of the bromine molecules cancel each other out.