What is the electron pair structure (electron geometry), shape (molecular shape), bond angle, bond polarity, and or molecular polarity for the following ions, compounds, or molecules? SiCL4 SF4
you'd start w/ the lewis structure and then make the electron pair structure + and molecular shape based on the number of bonds and lone pairs
|dw:1540103900836:dw|
rip well whenever you get back, for SiCl4 I got 4 bonds + 0 lone pairs, so what would that be
|dw:1540161547971:dw|
Whenever you get back ! =)
Si = 4 valence electrons Cl = 7 valence electrons so 4 + 4(7) = 32 electrons = 16 pairs so you need to fill up all lone pairs on chlorines. there shouldn't be any leftover electrons on silicon
|dw:1540164298779:dw|
anyway, so that's 4 bonds and 0 lone pairs on the central atom (only consider lone pairs on the central atom for this) so the electron geometry and shape are both tetrahedral, bond angle is 109.5 degrees bond polarity, well, idk if they're looking for a quantitative or qualitative response, you would have to check your textbook for the electronegativity values of S and Cl and subtract them, then classify the bond between S and Cl based on that the overall molecule is nonpolar since the bond polarities cancel out (4 equal bonds)
still there?
Yes i am
so fro bond polarity i would just say that they cancel out
\(\color{#0cbb34}{\text{Originally Posted by}}\) @Vocaloid bond polarity: you would have to check your textbook for the electronegativity values of Si and Cl and subtract them, then classify the bond between Si and Cl based on that \(\color{#0cbb34}{\text{End of Quote}}\)
electornegstivity for Si is 1.9
cl is -3
should be +3
then you'd subtract 3 - 1.9 and check your book to see how your book classifies it (polar, nonpolar, covalent, etc.)
nonpolar
=1.1
|dw:1540167638922:dw| your book might be slightly different but an electronegativity difference of 1.1 should put it into the polar not nonpolar category
so the bond polarity = polar, while the overall molecule polarity = nonpolar
you'll repeat this process for SF4
|dw:1540171221123:dw|
sulfur (6 valence) fluorine (7 valence) so 6 + 4(7) = 34, or 17 pairs of electrons, so there should only be 1 electron pair on the central atom
is it good otherwise
yes
then check the chart for the number of lone pairs and bonds to see what the electron and molecular geometries are https://s-media-cache-ak0.pinimg.com/736x/62/14/b5/6214b5e947f25877e06d9ac7654ee088.jpg
so four bonds 0 lone pairs. geometry and shape are tethrahedral bond angle is 109.5
there's a lone pair on the central atom, so 1 lone pair not 0.
the geometry and shape are tetrahedral?
check the chart again
4 bonds 1 lone pair.
trigonal bipyramid and seesaw
good bond angles for this one are complex but it's about ~90 deg, 180 deg, 120 degrees
then find the bond polarity based on the EN's of S and F
2.58 and 3.98
alright so what's the EN difference?
which one do you subtract from? The most electronegative?
higher value - lower value yes
3.98-2.58=1.4
good so what kind of bond would this be? polar, nonpolar, etc.?
polar covalent
good any ideas about the whole molecule's polarity? as a hint consider the lone electron pair on the central atom
IOnic?
is the whole molecular polar or nonpolar?
polar so nonpolar=?
the whole molecule is polar, (due to the lone e' pair) so that's it
Join our real-time social learning platform and learn together with your friends!