Answer:
Polar molecules- NH3, HBr
Nonpolar molecules- CO2, BF3, H2, CH4
Step-by-step explanation:
NH3 is polar because the three N-H bonds are in non symmetrical trigonal pyramidal arrangement, hence there is a resultant dipole moment that makes the molecule polar. The electro negativity difference between hydrogen and bromine makes HBr a polar molecule.
CO2 and BF3 are non polar because the individual dipoles in the molecule cancels out. CH4 is composed of two atoms of almost similar electro negativities hence it is non polar. H2 is contains a homonuclear covalent bond hence the molecule is nonpolar.