Structure and Bonding

Give the ground-state electron configuration for each of the following elements: 

How many electrons does each of the following elements have in its outermost electron shell?

Draw a molecule of chloroform, CHCl3, using solid, wedged, and dashed lines to show its tetrahedral geometry?

Convert the following representation of ethane,C₂H₆ , into a conventional drawing that uses solid, wedged, and dashed lines to indicate tetrahedral geometry around each carbon (gray 5 C, ivory 5 H).

                                                          Ethane

What are likely formulas for the following substances? 

(a)  CCl_? (b)AlH_?   (c) CH_?Cl₂ (d)SiF_?  (e) CH₃N_? 

Write line-bond structures for the following substances, showing all nonbonding electrons:

 (a) CHCl₃, chloroform (b) H₂S, hydrogen sulfide (c) CH₃NH₂ , methylamine (d) CH₃Li, methyllithium

Why can’t an organic molecule have the formula (C₂H₇)?

Draw a line-bond structure for propane, $\mathbf{CH}\mathbf{3}\mathbf{CH}\mathbf{2}\mathbf{CH}\mathbf{3}$. Predict the value of each bond angle, and indicate the overall shape of the molecule.

Convert the following molecular model of hexane, a component of gasoline, into a line-bond structure (gray 5 C, ivory 5 H).

HEXANE

Following is a molecular model of aspirin (acetylsalicylic acid). Identify the hybridization of the orbitals on each carbon atom in aspirin, and tell which atoms have lone pairs of electrons (gray 5 C, pink 5 O, ivory 5 H).   

                                 
 Aspirin (acetylsalicylic acid)

Draw a line-bond structure for propene, ${\mathbf{CH}}_3\mathbf{CH}\mathbf{=}{\mathbf{CH}}_2$. Indicate the hybridization of the orbitals on each carbon, and predict the value of each bond angle.

Question: Draw a line-bond structure for 1, 3-butadiene ${\mathbf{H}}_{\mathbf{2}}\mathbf{C}\mathbf{=}\mathbf{CH}\mathbf{-}\mathbf{CH}\mathbf{=}{\mathbf{CH}}_{\mathbf{2}}$. Indicate the hybridization of the orbitals on each carbon, and predict the value of each bond angle.

Draw a line-bond structure for propyne, ${\mathbf{CH}}_3\mathbf{C}\equiv \mathbf{CH}$ . Indicate the hybridization of the orbitals on each carbon, and predict a value for each bond angle.

Identify all nonbonding lone pairs of electrons in the following molecules, and tell what geometry you expect for each of the indicated atoms.

1. The oxygen atom in dimethyl ether,  ${\mathbf{CH}}_3{\mathbf{OCH}}_3$.
2. The nitrogen atom in trimethyl amine, $\mathbf{N}{\mathbf{\left(}{\mathbf{CH}}_3\mathbf{\right)}}_3$.
3. The phosphorus atom in phosphine, ${\mathbf{PH}}_3$.
4. The sulfur atom in the amino acid methionine, ${\mathbf{CH}}_3\mathbf{-}\mathbf{S}\mathbf{-}{\mathbf{CH}}_2\mathbf{-}{\mathbf{CH}}_2\mathbf{-}\mathbf{CH}\mathbf{\left(}{\mathbf{NH}}_2\mathbf{\right)}\mathbf{-}\mathbf{COOH}$ .

Tell how many hydrogens are bonded to each carbon in the following compounds, and give the molecular formula of each substance:

a.

b.

Propose skeletal structures for compounds that satisfy the following molecular formulas. There is more than one possibility in each case.

(a)  ${\mathbf{C}}_5{\mathbf{H}}_{12}$

(b)  ${\mathbf{C}}_2{\mathbf{H}}_7\mathbf{N}$

(c)  ${\mathbf{C}}_3{\mathbf{H}}_6\mathbf{O}$

 (d) ${\mathbf{C}}_4{\mathbf{H}}_9\mathbf{Cl}$

The following molecular model is a representation of para-aminobenzoic acid (PABA), the active ingredient in many sunscreens. Indicate the positions of the multiple bonds, and draw a skeletal structure (gray 5 C, red 5 O, blue 5 N, ivory 5 H).

Draw a line-bond structure for vinyl chloride,C₂H₃Cl , the starting material from which PVC [poly(vinyl chloride)] plastic is made

Draw a three-dimensional representation of the oxygen-bearing carbon atom in ethanol, using the standard convention of solid, wedged, and dashed lines.

Draw structures for the following molecules, showing lone pairs:

 (a) Acrylonitrile, C₃H₃N, which contains a carbon-carbon double bond and a carbon-nitrogen triple bond

 (b) Ethyl methyl ether,C₃H₈O, which contains an oxygen atom bonded to two carbons 

(c) Butane, C₄H₁₀, which contains a chain of four carbon atoms 

(d) Cyclohexene,C₆H₁₀ , which contains a ring of six carbon atoms and one carbon-carbon double bond

Draw structures for the following molecules, showing lone pairs:

 (a) Acrylonitrile, C₃H₃N , which contains a carbon-carbon double bond and a carbon-nitrogen triple bond

 (b) Ethyl methyl ether,C₃H₈O, which contains an oxygen atom bonded to two carbons 

(c) Butane,C₄H₁₀ , which contains a chain of four carbon atoms 

(d) Cyclohexene,C₆H₁₀ , which contains a ring of six carbon atoms and one carbon-carbon double bond

Draw structures for the following molecules, showing lone pairs:

 (a) Acrylonitrile,C₃H₃N , which contains a carbon-carbon double bond and a carbon-nitrogen triple bond

 (b) Ethyl methyl ether,C₃H₈O, which contains an oxygen atom bonded to two carbons 

(c) Butane,C₄H₁₀ , which contains a chain of four carbon atoms 

(d) Cyclohexene, C₆H₁₀ , which contains a ring of six carbon atoms and one carbon-carbon double bond

Draw structures for the following molecules, showing lone pairs:

 (a) Acrylonitrile,C₃H₃N which contains a carbon-carbon double bond and a carbon-nitrogen triple bond

 (b) Ethyl methyl ether,C₃H₈O, which contains an oxygen atom bonded to two carbons 

(c) Butane,C₄H₁₀ , which contains a chain of four carbon atoms 

(d) Cyclohexene,C₆H₁₀ , which contains a ring of six carbon atoms and one carbon-carbon double bond

Potassium methoxide,,KOCH₃ contains both covalent and ionic bonds. Which do you think is which?

What is the hybridization of each carbon atom in acetonitrile?

What is the shape of benzene, and what hybridization do you expect for each carbon?

Benzene

What kind of hybridization do you expect for each carbon atom in the following molecules?

(a)

                                               Procaine

(b)

                                             Vitamin C(Ascorbic acid)

Convert the following structures into skeletal drawings

(a)

                                          Indole

Convert the following structures into skeletal drawings

(b)

                                                1,3-pentadiene

Convert the following structures into skeletal drawings

(c) 

                                   1,2-dicholorcyclopentane

Convert the following structures into skeletal drawings

(d)

                                               Benzoquinone

Tell the number of hydrogens bonded to each carbon atom in the following substances, and give the molecular formula of each:

(a)

Tell the number of hydrogens bonded to each carbon atom in the following substances, and give the molecular formula of each

(b)

Tell the number of hydrogens bonded to each carbon atom in the following substances, and give the molecular formula of each:

(c)

Quetiapine, marketed as Seroquel, is a heavily prescribed antipsychotic drug used in the treatment of schizophrenia and bipolar disorder. Convert the following representation into a skeletal structure, and give the molecular formula of quetiapine.

the platelet aggregation inhibitor clopidogrel, marketed as Plavix. Give the molecular formula of each

                                 Clopidogrel (Plavix)

Why do you suppose no one has ever been able to make cyclopentyne as a stable molecule?

                               cyclopentyne

The following model is a representation of citric acid, the key substance in the so-called citric acid cycle, by which food molecules are metabolized in the body. Only the connections between atoms are shown; multiple bonds are not indicated. Complete the structure by indicating the positions of multiple bonds and lone-pair electrons (gray 5 C, red 5 O, ivory 5 H).

The following model is a representation of aspartame, C14H18N2O5, known commercially under many names, including NutraSweet. Only the connections between atoms are shown; multiple bonds are not indicated. Complete the structure for aspartame, and indicate the positions of multiple bonds (gray 5 C, red 5 O, blue 5 N, ivory 5 H)

Pyridoxal phosphate, a close relative of vitamin ${\mathbf{B}}_6$ , is involved in a large number of metabolic reactions. Tell the hybridization, and predict the bond angles for each nonterminal atom?

Pyridoxal phosphate

Draw an electron-dot structure for acetonitrile, , which contains a carbon-nitrogen triple bond. How many electrons does the nitrogen atom have in its outer shell? How many are bonding, and how many are nonbonding?

Propose structures for molecules that meet the following descriptions:

 (a) Contains two sp²-hybridized carbons and two sp³-hybridized carbons 

 (b) Contains only four carbons, all of which are sp²  -hybridized

 (c) Contains two sp-hybridized carbons and two sp² -hybridized carbons

How many valence electrons does each of the following dietary trace elements have?

(a) Zinc (b) Iodine (c) Silicon (d) Iron

Complete the electron-dot structure of caffeine, showing all lone-pair electrons, and identify the hybridization of the indicated atoms.

A carbanion is a species that contains a negatively charged, trivalent carbon.

(a) What is the electronic relationship between a carbanion and a trivalent nitrogen compound such as NH₃?

(b) How many valence electrons does the negatively charged carbon atom have? 

(c) What hybridization do you expect this carbon atom to have? 

(d) What geometry is the carbanion likely to have? 

Divalent carbon species called carbenes are capable of fleeting existence. For example, methylene, :CH2, is the simplest carbene. The two unshared electrons in methylene can be either paired in a single orbital or unpaired in different orbitals. Predict the type of hybridization you expect carbon to adopt in singlet (spin-paired) methylene and triplet (spin-unpaired) methylene. Draw a picture of each, and identify the valence orbitals on carbon.

There are two different substances with the formula ${\mathbf{C}}_{\mathbf{4}}{\mathbf{H}}_{\mathbf{10}}$. Draw both, and tell how they differ.

Give the ground-state electron configuration for each of the following elements:

Give the ground-state electron configuration for each of the following elements:

(b)

Give the ground-state electron configuration for each of the following elements:

(c)