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Acid and Base Organic Chemistry

Industrial Scale Synthesis

If you were carrying out an industrial scale synthesis in which one step involve a haloform reaction to convert a methyl ketone into the corresponding acid having one less carbon atom, would you use NaOH and Cl2, NaOH and Br2, or NaOH and I2 reagent? Give reasons for your choice.

N,N-dimethylaniline reagent

The formation of an azo compound is a slow reaction, but that rate can be increased by raising the pH of the solution. Why is this necessary? In other words, how does the pH of the solution affect the reactivity of the N,N-dimethylaniline reagent.

Predict the Product

What product would you expect to obtain from reaction of one equivalent of propanol with phthalic anhydride?

Acidic Species

Predict which of the following species is the most acidic. Explain. (A) Phthalimide (B) Benzamide

Simple Dissociation Acetic Acid

The dissociation pK for acetic acid is 4.76. Suppose that we dissolve a mole of this weak acid in 10L of water. Find the pH of the resulting solution. What fraction of acetic acid molecules dissociated?

Preparation of Esters in an Experiment

Consider the following reaction: Lauric acid + Ethanol yields Ethyl laurate + Acetic acid In the preparation of the esters given in this reaction, the reaction product is extracted with 5% sodium bicarbonate solution (NaHCO3) in the isolation step. Why? What gas is evolved during this washing step? Write a balanced equatio

Method for Trapping a Gas

The decomposition of 3-sulfolene to form 1,3-butadiene generates 1 mole of sulfur dioxide gas per mole of 1,3-butadiene. Substantial quantities of SO2 would be generated if this decomposition were carried out on a large scale. Suggest a method for trapping the gas to prevent its escape into the environment.

Sulfuric Acid as a Catalyst

Concentrated sulfuric acid is used as a catalyst for the esterification of acetic acid in the preparation of isopentyl acetate. Why is sulfuric acid needed if another acid, acetic acid, is already present?

Calculate the pKa of a buffer.

An unknown compound X, is thought to have a carboxyl group with a pka of 2.0 and another ionizable group with a pka between 5 and 8. When 75 ml of 0.1 M NaOH was added to 100 ml of a 0.1 m solution of X at pH 2.0, the pH increased to 6.72. Calculate the pKa of the second ionizable group of X.

Chemical Tests

A. What chemical tests might be used to ditinguish between pentanal and 2-pentanone; between benzyl alcohol and diphenylmethanol? b. Pinacol upon heating in aqueous acid, rearranges to form pinacolone. Suggest a mechanism for this reaction.

Haloform and Conversion

a. If you were carrying out an industrial scale synthesis in which one step involved a haloform reaction to convert a methyl ketone into the corresponding acid having one less carbon atom, would you use NaOH and Cl2, NaOH & Br2, or NaOH and I2 reagent? Give reasons. b. Write a balanced equation for the conversion of C6H5CHO

Creating chemical equations

A. Sodium bisulfite solution is added to an experiment at the end in order to destroy the unreacted bromine. What reaction is occurring here? Is HSO3- acting as an oxidizing or reducing agent? Write a balanced equation. b. Write equations to show how nitronium ions might be formed using a mixture of nitric and sulfuric acids.

Which is more acidic, phthalimide or benzamide?

A. Predict which of the following species is the most acidic, phthalimide or benzamide. Explain. b. What product would you expect to obtain from the reaction of one equivalent of propanol with phthalic anhydride?

Product Structure Formulas

A. If 3-bromo-1-propanol is treated with NaOH, a compound of molecular formula C3H6) is formed. Suggest a structure for this product. b. What product(s) would you expect to form when tetrahydrofuran is treated with excess hydroiodic acid (HI)? c. Write a suitable mechanism for the cleavage of butyl isopropyl ether with HI at 1

Aldol Condensations

A. "Crossed" or "mixed" aldol condensations are practical for synthesis, if one of the aldehydes (or ketones) has no alpha-hydrogen atoms. Explain. b. In the aldol condensation, why might it be essential that the benzaldehyde contain no benzoic acid?

Using Acid Chlorides to Prepare Aromatic Ketones

Acid chlorides are used as electrophiles in the Friedel-Crafts reaction to prepare aromatic ketones. The reaction involves the transfer of an aromatic hydrocarbon with an acyl chloride in the presence of a lewis acid, such as AlCl3. Using this reaction, outline the reaction sequence you would use to prepare: a) ethyl phenyl k

Nucleophilic substitution Versus ethyl esters

Give an explanation of why acid chlorides are more reactive toward nucleophilic substitution than are the corresponding ethyl esters. (When considering the nature of the leaving group and the rate-determining step in an addition-elimination sequence).

Predict Chemical Reactions' Products

I am having difficulty predicting products of chemical reactions examples. Please review my work and give me feedback: AgNO3 + NaBrO3 -> AgO3 + NaNO3 + Br Hg2S + NH4NO3 -> Hg2N2H2 + SO3 Pb(OH)2 + CuNO3 -> PbNO3 + Cu(OH)2 Li + SnOH -> LiOH + Sn.

Spectroscopic Method

What spectroscopic method is best for distinguishing between isomeric compounds? Could you please give an example of how each of these would be interpreted. Valeric acid CH3(CH2)3COOH 3-methylbutanoic acid (CH3)2CHCH2COOH Pivalic acid (CH3)3CCOOH.

Synthesis of Compounds

Propose a method to carry out the following synthesis. Use inorganic reagents only. Show all reagents, relevant reaction conditions and synthetic intermediates. CH3(CH2)16COOH ---> CH3(CH2)COO(CH2)17CH3

Structural Formulas and Reactions

1. Draw the structural formula for ethanol, 2-propanol and 2-methyl2-propanol. 2. Write the reaction between sodium bicarbonate and benzoic acid. 3. Write the structure of ester derived from benzoic and methanol.

Acid Dissociation and Effusion

Hi, I need assistance with the following questions: 1) If the acid dissociation constant, Ksuba, for an acid HA is 8 x 10^-4 at 25 degree C, what percent of the acid is dissociated in a 0.50 M solution of HA at 25 degree C? 2) Equal numbers of moles of Hsub2(g), Ar(g), and Nsub2(g) are placed in a glass vessel at room tempe

Ratio: Plasma pH

Question: At the pH 7.1, what is the ratio of plasma (HCO3-) to (CO2) is?

Calculating Plasma pH

Question: A respiratory acidosis is partially compensated to pH 7.3. If pCO2 is 70 mmHg, the plasma (HCO3-) is what?