# chemistry

posted by Hol

I'm drawing a Lewis structure for hydrogen cyanide using nitrogen with a valency of 3. Would I still need 2 dots after the N or would this represent nitrogen valency 5?

You need the two extra electrons for N at the end. Only the electrons involved BETWEEN the elements are bonding electrons; the others are used to fill orbtials but not for bonding purposes. Here is how you determine it.
H has 1 electron in the outer shell.
C Has 4 electrons in the outer shell.
N has 5 electrons in the outer shell.

10 electrons total. So ALL 10 electrons must be used. AND you try to place them such that two electrons are in the H sphere and 8 electrons for the other two elements.
H:C:::N:
The terminal (unpaired) electrons on N are used to make 8 electrons for N but those two are not involved in bonding. You see H has 1 bond, C has 4, and N has 3 (two dots, that is electrons) are equivalent to one (-) bond or 4 electrons are equivalent to a double (=) bond or 6 electrons are equivalent to a triple bond (but I can't draw a triple bond on the computer.

## Similar Questions

1. ### chemistry

I need help in drawing a structual formula for hydrogen cyanide(HCN)and cyanogen(CN)2, the drawing has to bear in mind the valencies of hydrogen(1),nitrogen(3) and carbon (4), any help appreciated H:C:::N: :N:::C:C:::N: Check my thinking. …
2. ### CHEMISTRY

Given assumed valencies: H=1, N=3, & C=4 i am now required to draw the structural formulae of HYDROGEN CYANIDE and CYANOGEN. H:C:::N is the Lewis electron dot structure. If you want to use "sticks" as a bond instead of two electrons, …
3. ### Chem

Concerning compounds cyanogen, Hydrogen cyanide and sodium cyanide. Cyanogen = C2N2 (CN)2 Hydrogen Cyanide = HCN boils at 26C and yeilds an acid solution when added with water. Sodium Cyanide = empirical formula NaCN is a solid melts …
4. ### chemistry

I have to draw Lewis structures for hydrogen cyanide and cyanogen with nitrogen valency of three. Would I still need 2 dots after the N in hydrogen cyanide or would this represent nitrogen with a valency of 5?
5. ### Chem

Draw a Structural Formulae for Hydrogen Cyanide (HCN) and Cyanogen (C2N2 or CN2) Hydrogen = 1 Valency Nitrogen = 3 Valencies Carbon = 4 Valencies H-C(triple bond)N N(triple bond)C-C(triple bond)N Thank you And for a Lewis Structure …
6. ### Chemistry

I need some help to draw a Lewis structure for hydrogen cyanide + what is the noble gas?
7. ### Chemistry

For a lab experiment we have to draw the lewis structures of hydrides. 1) Carbon It asks for the formula of hydride. Total # of valence electrons and the lewis structure. Total electrons would be four. I am not sure what the formula …