Xenon is one of the noble gases, and is generally quite unreactive.in fact,it was long believed that all the noble gases were totally unable to form compounds.It came as quite a surprise,therefore,when it was discovered that some of its compounds could be made.A chemical formula for one of them is,XeF2. 1)Draw its geometric structure and mention the molecular shape. 2)use the Valence Shell Electron Pair Repulsion(VSEPR) theory to explain the shape in question above. 3)Write down the shape that you would expect from a molecule with a central atom that has three bonding pairs and lone pair of electrons? Also give an example.
1) To draw the geometric structure of XeF2, we first need to identify the central atom, which is xenon (Xe). Xenon has eight valence electrons. Fluorine (F) has seven valence electrons. Since we have two fluorine atoms, we get a total of 2 * 7 = 14 electrons from the fluorine atoms.
Next, we need to distribute these electrons around the central atom while minimizing electron repulsion. The central atom, xenon (Xe), will form single bonds with each of the two fluorine atoms (F). This means that we will use four electrons, leaving us with 14 - 4 = 10 electrons.
Finally, we place the remaining electrons as lone pairs on the xenon atom. Since we have 10 electrons left, we will distribute them as two lone pairs on the xenon atom. This gives us the final structure:
F
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F -- Xe -- F
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F
2) The molecular shape of XeF2 can be explained using the Valence Shell Electron Pair Repulsion (VSEPR) theory. According to VSEPR theory, electron pairs in the valence shell of the central atom repel each other and stay as far apart as possible, minimizing repulsion.
In the case of XeF2, the central xenon atom has two bonding pairs and two lone pairs of electrons. The repulsion between these electron pairs causes them to arrange themselves in a linear fashion. The lone pairs, being localized closer to the xenon atom, exert slightly more repulsion than the bonding pairs, which results in a slightly bent shape. So, the molecular shape of XeF2 is linear or bent.
3) A molecule with a central atom that has three bonding pairs and one lone pair of electrons would have a trigonal pyramidal shape. In this shape, the three bonding pairs arrange themselves in a flat triangle, while the lone pair occupies one of the corners of the pyramid.
An example of a molecule with this shape is ammonia (NH3). Nitrogen (N) is the central atom, with three hydrogen (H) atoms bonded to it. Nitrogen has five valence electrons, which are distributed as three bonding pairs and one lone pair. The three hydrogen atoms form covalent bonds with nitrogen, resulting in a trigonal pyramidal shape:
H
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H -- N -- H
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