Doc3.docxQ2.Which one of the following is the most likely value for the bond angle α shown in the diagram of SF4 below?
The anwser is A but i dont know why
(Sulfur bonded to 4 fluorine atoms, with a lone pair)
AQA AS chem, bonding question watch
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Last edited by X_alwayssmiley; 08-04-2016 at 16:16.
- 08-04-2016 16:15
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- 08-04-2016 23:02
Imagine that lone pair were another atom and think what shape molecule that would give, and the bond angles of such a shape - then remember than the influence of a lone electron pair causes bond angles to be slightly reduced against the shape with the same amount of electron domains but all bonded.
In this case it's got 5 electron domains - if all were bonded it would be trigonal bipyrimidal, with bond angles of 90° (axial to equatorial), 120° (eq to eq) and 180° (ax to ax). The angle α is between the two equatorial fluorine atoms, so would be 120°, but the lone pair causes that to be slightly reduced - so 118° would be a reasonable estimate for that bond angle.