Question

How do I know which part of a compund is negectivly charged and which side is positivly charged? In BH3 how would I know if the B is positivly charged or negetively charged? and for hydrogen?

Answer 1

H is 2.1. B is 2.0. Almost the same. I would write a delta delta (two small delta) + for B and a delta delta - for H. The delta delta + or - signifies an extremely small negative or positive charge. You can carry this when explaining to delta delta delta - and +.

Answer 2

Scroll down to the delta. Both the cap and the lower case are shown.
http://www.mathacademy.com/pr/prime/articles/greek/index.asp

Answer 3

For something that has 3 different elements how would I know which is positive and which is negetive? For exmaple HCN.

Answer 4

HCN is a linear moecule, H-CtriplebondN so you write H as the + end and CN as the negative end. If you are forced into breaking it down further, just use the electronegativities. H is 2.1, C is 2.4, and N is 3.0, so I would write H as +, N as negative, and C as delta delta +. When you get into the three dimensional arrangement of HCN and other polyatomic molecules, you will see how it is done spatially.

Answer 5

Why isnt the carbon negetive ?

Answer 6

But most polyatomic ions, as CN, SO4^=, CLO4^- etc are considered together not separately.

Answer 7

Ohhhh OK. Thank you :)

Answer 8

C is 2.4 and N is 3.0; therefore, N must be negative with respect to C. Then the H is 2.1 and it must be positive with respect to C. You see why trying to assign partial + or - charges to everything becomes problematic.

Answer 9

Ohh. Yes I do see that. Thanks :)