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### Is it best to memorize electronegativity?

Posted: Thu Nov 15, 2018 7:28 pm
If we don't "memorize" atom's electronegativity, is there a way to intuitively know what makes a polar vs nonpolar molecule?

### Re: Is it best to memorize electronegativity?

Posted: Thu Nov 15, 2018 7:31 pm
I assume there examples we will be given will have molecules with atoms of obviously different electronegativity, for example NH3 or H2O and we're not expected to know the exact electronegativity.

### Re: Is it best to memorize electronegativity?

Posted: Thu Nov 15, 2018 8:45 pm
I remember Professor Lavelle saying in class we did not need to know exact the exact values of electronegativity, but as long as we have an idea of them we should be absolutely fine.

### Re: Is it best to memorize electronegativity?

Posted: Thu Nov 15, 2018 9:12 pm
f electronegativity values are given, the difference in electronegativity values is 0.4 or greater, the bond is polar.

### Re: Is it best to memorize electronegativity?

Posted: Thu Nov 15, 2018 9:15 pm
Usually molecules with lone pairs tend to be polar, ex: trigonal pyramidal has 1 lone pair and is polar, unless the vsepr shape is non-symmetrical and in that case the bond would be non polar despite the lone pairs, ex: square planar has 2 lone pairs and is non-polar because it is symmetrical

### Re: Is it best to memorize electronegativity?

Posted: Thu Nov 15, 2018 11:34 pm
The farther two elements are on the periodic table, the more electronegativity difference between them.

### Re: Is it best to memorize electronegativity?

Posted: Sun Nov 18, 2018 11:17 pm
I believe Professor said that we should just have an idea of electronegativity, but not necessarily the exact values. However a basic rule is the farther elements are from each other on the periodic table, the more the electronegative difference is.

### Re: Is it best to memorize electronegativity?

Posted: Sun Nov 18, 2018 11:22 pm
I think it is important to know the general trend of electronegativity on the periodic table.

### Re: Is it best to memorize electronegativity?

Posted: Sun Nov 25, 2018 9:18 pm
I feel like some of the homework problems can only be done when given the exact number for electronegativity. Will it be obvious on the test?