# Lewis structure (Related! - )

1. Oct 1, 2009

### miss.strw

1. The problem statement, all variables and given/known data
Can you tell me if I am correct?Thank you so much!!!!!!I tried acd and ac but it's wrong! :(

1. Which of the following are true about the correct Lewis structure of the SeF2 molecule ?

a) The structure has 20 valence electrons.
b) One of the F atoms would be the central atom as it has a greater number of valence electrons than an Se atom.
c) Only the Se atom has an octet of electrons.
d) Although there are different ways to draw the structure, only one is correct.
The attempt at a solution
I tried acd and ac but it's wrong! :(

2. Which of the following molecules has a Lewis Structure that contains a multiple bond ?

a) Cl2

b) C2H2

c) CO

d) N2

e) SeF2

The attempt at a solution
I tried b, bd, bde, and be but it's all wrong! :( Help!

Last edited: Oct 1, 2009
2. Oct 1, 2009

### IBY

For number 1, look at the periodic table to know their valence electrons, and notice how two flourines are attached to the selenium. Notice how selenium has two holes, while each flouride has one hole. The one hole in the flourine leaves one lonely electron without a pair. Did you try actually drawing them? It helps. ^_^

3. Oct 1, 2009

### miss.strw

So the answer is a,d ONLY?

a) The structure has 20 valence electrons. (I calculated it it's is 20 valence)
b) One of the F atoms would be the central atom as it has a greater number of valence electrons than an Se atom. (It is Se not F)
c) Only the Se atom has an octet of electrons. (Se does not since u talk about the holes" electrons.)
d) Although there are different ways to draw the structure, only one is correct. (Not sure but maybe?)

Last edited: Oct 1, 2009
4. Oct 1, 2009

### miss.strw

Last edited: Oct 1, 2009
5. Oct 1, 2009

### IBY

A is certainly true, and D is probably true too. I do not see any other way to fill in the holes of all three atoms without that configuration.

6. Oct 2, 2009