Concept explainers
(a)
Interpretation:
Lewis structure, VSEPR formula, bond angle, and molecular shape for
Concept Introduction:
Valence Shell Electron Pair Repulsion model predicts shape by inclusion of bond angles and most distant arrangement of atoms that leads to minimum repulsion. For the molecules that have no lone pairs around the central atom the bonded-atom unshared -pair arrangement is decided by the table as follows:
In order to determine the shape the steps to be followed are indicated as follows:
- 1. Lewis structure of molecule should be written.
- 2. The type electron arrangement around the central atom should be identified around the central atom. This essentially refers to determination of bond pairs and unshared or lone pairs around central atoms.
- 3. Then bonded-atom unshared -pair arrangement that can maximize the distance of electron pairs about central atom determines the shape.
For molecules that have lone pairs around central atom, lone pairs influence shape, because there are no atoms at the positions occupied by these lone pairs. The key rule that governs the molecular shape, in this case, is the extent of lone –lone pair repulsions are far greater than lone bond pair or bond pair-bond pair repulsions. The table that summarized the molecular shapes possible for various combinations of bonded and lone pairs are given as follows:
(a)

Answer to Problem 2E.15E
The shape for
Explanation of Solution
Total valence electrons are sum of the valence electrons on each atom in
The skeleton structure in
These 12 electron pairs are allotted as lone pairs to satisfy respective octets. Hence, the Lewis structure in
It is evident that in
If central atom is represented by A, and other attached bond pairs by X, then for any tetrahedral species with no lone pairs the VSEPR formula is predicted as
(b)
Interpretation:
Lewis structure, VSEPR formula, bond angle, and molecular shape for
Concept Introduction:
Refer to part (a).
(b)

Answer to Problem 2E.15E
The shape for
Explanation of Solution
Total valence electrons are sum of the valence electrons on atom in
The skeleton structure in
These 13 electron pairs are allotted as lone pairs to satisfy respective octets. Hence, the Lewis structure in
It is evident that
One lone pair is localized on equatorial positions so as to minimize lone pair–bond pair repulsions in accordance with VSPER model. This leads see-saw shape for
If lone pairs are represented by E, central atom with A and other attached bon pairs by X, then for any see-saw species the VSEPR formula is predicted to be
(c)
Interpretation:
Lewis structure, VSEPR formula, bond angle and molecular shape for
Concept Introduction:
Refer to part (a).
(c)

Answer to Problem 2E.15E
The shape for
Explanation of Solution
Total valence electrons are sum of the valence electrons on atom in
The skeleton structure in
These 9 electron pairs are allotted as lone pairs or as multiple bonds to oxygen so as to satisfy octets. Hence, the Lewis structure in
It is evident that in
If lone pairs are represented by E, central atom with A and other attached bond pairs by X, then for any trigonal planar species the VSEPR formula is predicted as
(d)
Interpretation:
Lewis structure, VSEPR formula, bond angle and molecular shape for
Concept Introduction:
Refer to part (a).
(d)

Answer to Problem 2E.15E
The shape for
Explanation of Solution
Total valence electrons are sum of the valence electrons on atom in
Thus, Lewis structure in
It is evident that in
Lone pair tend to be localized on apical position and so
If lone pairs are represented by E, central atom with A and other attached bond pairs by X, then for any trigonal pyramidal species the VSEPR formula is predicted as
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Chapter 2 Solutions
ACHIEVE/CHEMICAL PRINCIPLES ACCESS 2TERM
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- In the drawing area below, draw the major products of this organic reaction: 1. NaOH ? 2. CH3Br If there are no major products, because nothing much will happen to the reactant under these reaction conditions, check the box under the drawing area instead. No reaction. Click and drag to start drawing a structure. ☐ : A คarrow_forwardPredict the major products of the following organic reaction: NC Δ ? Some important Notes: • Draw the major product, or products, of the reaction in the drawing area below. • If there aren't any products, because no reaction will take place, check the box below the drawing area instead. • Be sure to draw bonds carefully to show important geometric relationships between substituents. Note: if your answer contains a complicated ring structure, you must use one of the molecular fragment stamps (available in the menu at right) to enter the ring structure. You can add any substituents using the pencil tool in the usual way. Click and drag to start drawing a structure. Х аarrow_forwardPredict the major products of this organic reaction. Be sure you use dash and wedge bonds to show stereochemistry where it's important. + ☑ OH 1. TsCl, py .... 文 P 2. t-BuO K Click and drag to start drawing a structure.arrow_forward
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