which molecules are polar
Determine each atom's electronegativity from the table. You can determine a non polar molecule immediately if the molecules have equal electronegativity. A molecule can also be non polar if the structure of the atoms line up in a way that the outer orbital electrons cancel out electronegativity. Therefore, you need to examine the shape of the molecule. In general, V-shaped and pyramid-shaped molecules are polar. Water is polar because of the differences in the electronegativity between oxygen and hydrogen. Oxygen is highly negative compared to hydrogen.