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Topic: About Lewis Base!  (Read 6131 times)

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Offline Winga

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About Lewis Base!
« on: December 03, 2004, 09:59:24 PM »
A question is that it asks which one is a better Lewis Base, C4- or Si4-?

I don't know how to answer it!

Offline Donaldson Tan

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Re:About Lewis Base!
« Reply #1 on: December 04, 2004, 03:54:50 PM »
which of the two is more likely to loose electrons?

a lewis base is defined as an electron pair donor.
"Say you're in a [chemical] plant and there's a snake on the floor. What are you going to do? Call a consultant? Get a meeting together to talk about which color is the snake? Employees should do one thing: walk over there and you step on the friggin� snake." - Jean-Pierre Garnier, CEO of Glaxosmithkline, June 2006

Offline Winga

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Re:About Lewis Base!
« Reply #2 on: December 04, 2004, 10:42:54 PM »
Si^4- is larger in size, so the attraction between the nucleus and valence e-s is weaker and its e- cloud is more polarizable, therefore, Si^4- is easier to donate e-s.

But, to compare C^4- & Si^4- stability, C^4- should be more unstable than Si^4- because of its larger electron-electron repulsion.
If we compare the basicity of F- & I-, I- is not quite available to donate e- than F-, because I- is more stable than F-.

So, there seems to have 2 factors to explain this case, which one is dominant?

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