Generally if a molecule contains polar bonds and the bond dipole moments do not cancel each other out then that molecule will have an overall dipole moment. Bond dipoles arise when there is a significant difference in electronegativity between the atoms in the bond. There some cases such as phosphine PH3 where the lone pair can make a significant contribution to the molecular dipole moment.
Probably you are intending to question whether CCl4 has a dipole moment. if so the answer is no. it is because CCl4 is a symmetric molecule and hence even if each bond has a dipole moment, the algebraic sum of the dipole moments of all the four bonds cancel out resulting in zero dipole moment.
Net dipole
A molecule with two strong bond dipoles can have no molecular dipole if the bond dipoles cancel each other out by pointing in exactly opposite directions. For example, in carbon dioxide (a linear molecule), the carbon-oxygen bonds have a large dipole moment. However, because one dipole points to the left and the other points to the right, the dipoles cancel and overall there is no molecular dipole.
A molecule with two strong bond dipoles can have no molecular dipole if the bond dipoles cancel each other out by pointing in exactly opposite directions. For example, in carbon dioxide (a linear molecule), the carbon-oxygen bonds have a large dipole moment. However, because one dipole points to the left and the other points to the right, the dipoles cancel and overall there is no molecular dipole.
HBr has a dipole
dipole moments increase with the polarity
The more polar the molecule, the stronger the force.
All polar molecules have a permanent dipole moment, but London dispersion forces in non-polar molecules can cause temporary dipole moments as well.
The more polar the molecule, the stronger the force.
An IR Active stretch simply means that the vibrations of the molecule result in an overall dipole of the molecule. If a stretch has a dipole, it is IR active. If a stretch does not have a dipole. then it is IR Inactive.
The more polar the molecule, the stronger the force.
Probably you are intending to question whether CCl4 has a dipole moment. if so the answer is no. it is because CCl4 is a symmetric molecule and hence even if each bond has a dipole moment, the algebraic sum of the dipole moments of all the four bonds cancel out resulting in zero dipole moment.
Symmetric molecules have no dipole moment. An example is carbon tetrachloride, CCl4 , which has no dipole moment yet the C-Cl bonds are polar, (chlorine is more electronegative than carbon). The chlorine atoms each have a small negative charge but because the molecule is tetrahedral there is no dipole and therefore no dipole moment
An overall dipole moment is H2S.
Net dipole
Ion-dipole, Dipole-dipole, and Dipole-induced dipole.
A molecule with two strong bond dipoles can have no molecular dipole if the bond dipoles cancel each other out by pointing in exactly opposite directions. For example, in carbon dioxide (a linear molecule), the carbon-oxygen bonds have a large dipole moment. However, because one dipole points to the left and the other points to the right, the dipoles cancel and overall there is no molecular dipole.