Anonymous
Anonymous asked in Science & MathematicsChemistry · 1 decade ago

Chemistry Question: VSEPR model?

So I've been stuck on these 2 problems (with multiple parts of course) for a long time, and I can't figure them out. I would greatly appreciate any help with any of the questions, thanks!

2 Pairs L = Linear

3 Pairs TPL = Trigonal Planar

B = Bent

4 Pairs TET = Tetrahedral

TPY = Trigonal Pyramidal

B = Bent

5 Pairs TBP = Trigonal Bipyramidal

S = See-saw

T = T-shaped

L = Linear

6 Pairs O = Octahedral

SPY = Square Pyramidal

SQP = Square Planar

1) What is the label from the table above for the arrangement of both bonding and nonbonding electron domains around the central atom in ClOF4- predicted by the VSEPR/ED theory?

If it helps, the number of lone pair electrons on CLOF4- is 1.

2)What is the label from the table above for the actual structure of ClOF4- predicted by the VSEPR/ED theory?

3)According to valence bond theory, what hybridization of atomic orbitals on the central Cl atom in ClOF4- is necessary to accommodate the shape of ClOF4-?

Update:

1) What is the label from the table above for the arrangement of both bonding and nonbonding electron domains around the central atom in PF4- predicted by the VSEPR/ED theory?

If it helps again, the number of lone pair electrons is 1.

2)What is the label from the table above for the actual structure of PF4- predicted by the VSEPR/ED theory?

3)According to valence bond theory, what hybridization of atomic orbitals on the central P atom in PF4- is necessary to accommodate the shape of PF4-?

Update 2:

ya it is.. but I mean this was chemistry I did back in 10-11th grade in highschool... I'm sad that I can't remember any of it at this point..

2 Answers

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  • Anonymous
    1 decade ago
    Favorite Answer

    So for question 1:

    The first question asks what the geometry will be when you consider the bonding and nonbonding electrons, or, the bonding and lone pair electrons. To do this, we need to first draw a Lewis dot structure. Cl and F each have 7 valence electrons and O has 6, and there is a net -1 charge so you will have 7(5) + 6 + 1 = 42 valence electrons. Cl is the central atom and O and F form five separate bonds around it. The lewis dot structure will look something like this (sorry this didn't turn out so well. Cl should be in the center with O and F around it):

    O

    I

    F -- Cl -- F

    / I

    F F

    However, if you assume that all of the Fs and O have three lone pair (too hard to draw in!), this adds up to only 40 valence electrons. Thus, the Cl must have an additional lone pair:

    O ..

    I /

    F -- Cl -- F

    / I

    F F

    We can see from this lewis dot structure, which now correctly has 42 electrons, that the Cl has six groups surrounding it (5 bonds and a lone pair). If you look at the chart you posted above, this is an octahedral.

    The second question asks what the actual structure is. Basically, this is just asking what we will see as the structure of the atom. We cannot actually see the lone pair but it still takes up space and impacts the shape of the molecule. The lone pair takes up more room than a bonding pair and therefore decreases the bond angles of the other atoms. The actual structure will be square pyramidal. Look at the chart on this link - it is very helpful:

    http://intro.chem.okstate.edu/1314F00/Lecture/Chap...

    As you can see, 5 bonding pair and 1 lone pair is a square pyramidal.

    The final question asks about the hybridization. Since the LDS shows that this molecule has 6 groups surrounding it (the lone pair counts as a group), it will be d2sp3 hybridized. This hybridization has 6 hybrid orbitals that will accommodate the six orbitals involved in bonding. There's a chart on this site that tells what hybridization goes with what structure:

    http://www.science.uwaterloo.ca/~cchieh/cact/c120/...

    The second problem is the same thing. Draw the lewis dot structure and use the two tables to determine the actual structure and hybridization. Hope that helps!

  • Anonymous
    1 decade ago

    sorry dude, I'm stumped already. Is this college chemistry?

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