Chemistry Discussion Response

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Your Name:

Structure Influences Acidity and Basicity Read the instructions carefully and answer the following questions in the space provided. Then attach the PDF file on Discussion Board for peer discussion and peer review 1. In one or two sentences or with an illustration, discuss how each of the

four factors below play a role in determining relative acidity strength. In other words, discuss the general trends, be concise and specific.

a. Periodic Trends b. Resonance c. Induction d. Orbitals

1.acidic strenth increases more down the group

compared to the left / right movement in a period. A bond polarity will determine the relative acidity

strength in binary acids through a period. the increase of electronegativity in the atom, the

higher the bond polarity / stronger the acid. The size of the atoms increases down the groups as

well as the bond strenth.

2. resonance can increase the overall strtenth on a acid.

3. induction the inductive effect. the inductive effect increases as the elctronegavity does. the group

inductive effect decreases down the group. going down on the group

inductive effect decreases while the acidty increases. the inductive

increases the electron density and the acid weakens while as the negative effect will decreases

electron density. 4. orbitals the sp orbital is the

highest electrongetivity and sp3 is the least. the speherical shape of s

orbital demonstrates the force of attraction from the nucleues. the

electrons are more tightly bound as the increasement of electrongetivity.

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2. Analyze the two compounds below. Circle the structure which is most

acidic overall. Discuss the factors that led you to this choice.

3. Analyze the structure below. Circle the nitrogen atom which is considered

to be overall most basic. Provide a brief discussion to explain why this nitrogen is considered to be most basic (hint: think about the orbital each nitrogen lone-pair occupies). Draw relevant resonance structures of the conjugate acid expected to form when this structure is treated with 1 equivalent of HCl. Underline the resonance structure(s) that have filled octets everywhere.

Discussion:

Discussion:

the stablization of the carboxylate anion is caused from the increasement of

acidity from negative inductive effects. the distance of the COOH group decreases with the effect of the

inductive effect. the carboylate anion is stablized from the withdrawing of group

F at alpha position.

basicity depends on the avalibility of the

electrons for lone pair donation. this nitrogen has a lone pair in the p

orbital without any. paarticipation in the

conjugation. the conjugate acid is stablized by two nitrogen atoms.

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4. The pKa of the most acidic CH2 group in each of the following compounds

was measured in DMSO as solvent (reference: J. Org. Chem. 1981, 46, 4327–4331.)

Given the pKa data above, propose an explanation why compound 1 is more acidic than compound 3.

Draw the conjugate acid formed and its other relevant resonance structures

Text

the H+ concernatrion is less in cmopound 3 than compound 1. tess kpa has more ka volume.

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Given the pKa data above, propose which of the following two compounds below (5 or 6) is more acidic by comparing the stability of the corresponding conjugate bases. Include (ie. draw) all relevant resonance contributors in your discussion. Do any resonance structures have greater contribution than others to the overall stability? Underline the resonance structure that is considered to be most stable overall.

compound 6 is more acidic the weaker conjugate base is more acidic. the lower the pKa has the stronger acid. the charge is spread out over a less electronegative carbon in compound

5 this results in less stabilzation. compound 6 spread the charge over the electrongative oxygen. this causes a more stab.e base and a more acidic compound.

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