Electronegativity and bond polarity

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Category:

Education

Tags:

• electronegativity
• and
• bond
• polarity
• polar
• non
• periodic
• trends

[sakka4goodz]

I have an issue with NO2-

I know its polar, I heard from another instruction video that Bent and Trigonal Pyramid are polar.

So how would my net dipole be described? Straight down between the 2 oxygens?

[TheScienceChannel1]

The NO2- wouldn't be trigonal planar because the two electrons take up more space by repulsion and force the oxygens off at an odd angle. Because of this odd angle, the molecule will have a net dipole. Electronegativity comes in to determine the dipole direction. Trigonal pyramidal structures tend to have 3 alike groups attached to a central molecule... for example BF3, where 3 flourines would be attached to a boron equally. Because all F's are equally spaced equally, no net dipole exists.

[TheScienceChannel1]

@sakka4goodz Sorry for the late response, but hope this helps--

You would be correct on describing the net dipole as straight down between the 2 oxygens. All bent structures will be polar by nature. This is because a lone pair of electrons "bend" the two other groups attached to a central molecule, hence the name "bent". In the example of NO2-, the lone pair of electrons on the nitrogen bend the two oxygens.

[kutecurse6060]

naaaaaaaaaaice explanation..bt the way u hold the marker is very much distraactinnnn :D