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2.E: Polar Covalent Bonds; Acids and Bases (Exercises)

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    61689
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    These are the homework exercises to accompany the Textmap for McMurry's Organic Chemistry textbook.

    2.1 Polar Covalent Bonds: Electronegativity

    2.1 Exercises

    Questions

    Q2.1.1

    Rank the following from least polar to most polar using knowledge of electronegativity

    CH3CH2-Li CH3CH2-K CH3CH2-F CH3CH2-OH

    Solutions

    S2.1.1

    (least polar) OH < F < Li < K (most polar)

    2.2 Polar Covalent Bonds: Dipole Moments

    2.2 Exercises

    Questions

    Q2.2.1

    The following molecule has no dipole moment in the molecule itself, explain.

    2.2 rev.png

    Q2.2.2

    Which of the following molecules has a net dipole?

    2.2(2).png

    Q2.2.3

    Within reactions with carbonyls, such as a reduction reaction, the carbonyl is attacked from the carbon side and not the oxygen side. Using knowledge of electronegativity explain why this happens.

    2-2-3.png

    Solutions

    S2.2.1

    The hydroxyl groups are oriented opposite of one another and therefore the dipole moments would “cancel” one another out. Therefore having a zero net-dipole.

    S2.2.2

    1, 3, and 4 have a net dipoles.

    S2.2.3

    The oxygen is more electronegative than the carbon and therefore creates a dipole along the bond. This leads to having a partial positive charge on the carbon and the reduction can take place.

    2-2-3sol.png

    2.3: Formal Charges

    2.3 Exercises

    Questions

    Q2.3.1

    Give the formal charges for all non-hydrogen atoms in the following molecules: \(\ce{BH4^{-}}\), \(\ce{H2O}\), \(\ce{CH3O^{-}}\)

    Solutions

    S2.3.1

    BH4 (B = −1)

    H2O (O = 0)

    CH3O (C = 0, O = −1)

    2.4 Resonance

    2.4 Exercises

    Questions

    Q2.4.1

    Draw the resonance structures for the following molecule:

    2-4qu.png

    Solutions

    S2.4.1

    2.4.png

    2.5 Rules for Resonance Forms

    2.5 Exercises

    Questions

    Q2.5.1

    Are all the bond lengths the same in the carbonate ion, CO32-?

    2-5sol.png

    Solutions

    S2.5.1  Yes, the bond lengths in carbonate ion are all the same.  Carbonate ion exists as the resonance hybrid of the three resonance forms below.

    2-5qu.png

    2.7 Acids and Bases: The Brønsted-Lowry Definition

    2.7 Exercises

    Questions

    Q2.7.1

    Is the following molecule a Brønsted acid or base?

    HSO4

    Solutions

    S2.7.1

    It can be both, consider the following schemes:

    2.7.png

    2.9 Predicting Acid-Base Reactions from pKaKa Values

    2.9 Exercises

    Questions

    Q2.9.1

    In the following reactions give the resulting products and label the conjugate acid and bases.

    2-9qu.png

    Solutions

    S2.9.1

    2.9.png

    2.10 Organic Acids and Organic Bases

    2.10 Exercises

    Questions

    Q2.10.1

    Determine which of the one of the molecules is an acid or a base.

    2.10.png

    Solutions

    S2.10.1

    1 = Base

    2 = Acid

    3 = Acid

    4 = Acid

    2.11 Acids and Bases: The Lewis Definition

    2.11 Exercises

    Questions

    Q2.11.1

    For the following molecules state wither they are Lewis acid or base and wither or not they are a Brønsted acid or base.

    2.11.png

    Solutions

    S2.11.1

    Acetone is a Lewis base and a Brønsted base. Ammonium cation is both a Lewis acid and a weak Brønsted acid.


    2.E: Polar Covalent Bonds; Acids and Bases (Exercises) is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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