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Polar/Nonpolar

My chem teacher gave us simple guidelines to check if an equation is polar.

he says if it has Oxygen and Nitrogen: Polar
if it has Carbon & Hydrogen: Nonpolar
has Cl & F (not symmetrical) Polar
symmetrical: Not polar

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if thats so how can CH3OH be polar?
and how can you know if a problem is symmetrical?

anyone have any tips on knowing if an equation is polar?

Instead of remembering all those guidelines
i suggest you understand the logic

if in a molecule one element has more electronegativity then the other
then it acquires a partial negative charge....and so the molecule becomes polar

in CH3OH, oxygen is more electronegative than hydrogen
therefore, O acquires partial negative charge and H acquires partial positive charge
making the molecule polar

im not sure i understand, isnt there always one element thats more electronegative? how will i know when it makes it polar?

u should first understnad electronegativity concept how electronegativity varies along the group and periods in the periodic table.

and then learn about polarity and non polarity

i know that it increase up and to the right, F is most electronegative, excluding noble gases.