What is the difference between polar molecule and polar bonds?

Question

aaronq · Answer

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if you add up the dipoles (they are vectors), the net result in zero.

anonymous · Answer

I understand that thanks, but we aren't going to be given an electronegative chart. How are we supposed to determine if its a polar bond w/o the chart?

aaronq · Answer

i guess you have to memorize some common polar bonds. :S

if you know the position of the elements you're dealing with you can estimate it, since the trend is that electronegativity increases and you go up a group and down a row:|dw:1382229215002:dw|