Collection of chemistry questions from textbook.

Understand the Problem

The image contains several chemistry questions related to organic reactions, thermodynamics, and electrochemistry. Questions range from arranging compounds by boiling point to explaining reaction mechanisms and defining protein structures. Let's classify the questions.

Answer

The answers to questions 22-31 have been provided. Includes chemistry concepts such as: boiling points, reaction mechanisms, organic reaction products, glycosidic linkages, protein structure, molar conductivity, electrochemistry, valence bond theory, reaction rates, and alcohol reactions.

(a) The increasing order of boiling point is: 2-Chloro-2-methylpropane < 2-Chlorobutane < 1-Chloropropane < 1-Chlorobutane. (b) S_N1 reactions are unimolecular, proceeding in two steps with a carbocation intermediate, favored by tertiary alkyl halides, while S_N2 reactions are bimolecular, occurring in one step with a transition state, and favored by primary alkyl halides.
(i) Ethanol heated with alumina at 633 K yields ethene (dehydration). (ii) Propanone treated with methyl magnesium iodide and hydrolyzed yields 2-methylpropan-2-ol (a tertiary alcohol).
A glycosidic linkage is a covalent bond that joins a carbohydrate (sugar) molecule to another group, which can be another carbohydrate.
(a) A peptide bond is an amide bond formed between the carboxyl group of one amino acid and the amino group of another. (b) Denaturation is the process in which proteins or nucleic acids lose their quaternary structure, tertiary structure, and secondary structure which is present in their native state, by application of some external stress or compound such as a strong acid or base, a concentrated inorganic salt, an organic solvent or heat.
Molar conductivity is calculated using the formula Λm = κ/C, where κ is the conductivity and C is the molar concentration. Conductivity κ = 1/R * (l/A), where R is resistance, l is the distance between electrodes, and A is the area of the cross-section. Given R = 50 ohm, l = 2.0 cm, A = 4.0 cm², and C = 0.5 mol/L. First, calculate κ = (1/50) * (2/4) = 0.01 ohm⁻¹cm⁻¹. Then, convert the concentration to mol/cm³: C = 0.5 mol/L = 0.5 mol/1000 cm³ = 0.0005 mol/cm³. Finally, Λm = 0.01/0.0005 = 20 ohm⁻¹cm²mol⁻¹.
The salt bridge in an electrochemical cell maintains electrical neutrality by allowing ions to flow between the half-cells, preventing charge buildup that would stop the reaction.
[Cr(NH₃)₆]³⁺: Chromium is in +3 oxidation state, Cr³⁺ has a d³ configuration. NH₃ is a strong field ligand, causing pairing of electrons. The complex has an octahedral geometry with hybridization d²sp³. It is paramagnetic due to the presence of unpaired electrons.
Given: 4NH₃ + 5O₂ → 4NO + 6H₂O, and the rate of increase of NO is 0.18 mol in 50 sec. (i) Rate of reaction = (1/4) * (Δ[NO]/Δt) = (1/4) * (0.18/50) = 0.0009 mol/s. (ii) Rate of formation of H₂O = (6/4) * (Δ[NO]/Δt) = (6/4) * (0.18/50) = 0.0054 mol/s. (iii) Rate of disappearance of NH₃ = (Δ[NO]/Δt) = 0.18/50 = 0.0036 mol/s.
(i) Isopropyl chloride treated with alcoholic KOH undergoes dehydrohalogenation to form propene. (ii) Methyl bromide treated with sodium in dry ether undergoes Wurtz reaction to form ethane. (iii) Methyl chloride treated with KCN forms methyl cyanide (acetonitrile), which upon hydrolysis with dil. HCl gives acetic acid.
(a) Ethanol with HBr: C₂H₅OH + HBr → C₂H₅Br + H₂O Ethanol with HI: C₂H₅OH + HI → C₂H₅I + H₂O (b) Dehydration of alcohols to form alkenes is carried out with conc. H₂SO₄ because H₂SO₄ acts as a dehydrating agent and doesn't act as an oxidizing agent conc. HCl or HNO₃ might.

Answer for screen readers

(a) The increasing order of boiling point is: 2-Chloro-2-methylpropane < 2-Chlorobutane < 1-Chloropropane < 1-Chlorobutane. (b) S_N1 reactions are unimolecular, proceeding in two steps with a carbocation intermediate, favored by tertiary alkyl halides, while S_N2 reactions are bimolecular, occurring in one step with a transition state, and favored by primary alkyl halides.
(i) Ethanol heated with alumina at 633 K yields ethene (dehydration). (ii) Propanone treated with methyl magnesium iodide and hydrolyzed yields 2-methylpropan-2-ol (a tertiary alcohol).
A glycosidic linkage is a covalent bond that joins a carbohydrate (sugar) molecule to another group, which can be another carbohydrate.
(a) A peptide bond is an amide bond formed between the carboxyl group of one amino acid and the amino group of another. (b) Denaturation is the process in which proteins or nucleic acids lose their quaternary structure, tertiary structure, and secondary structure which is present in their native state, by application of some external stress or compound such as a strong acid or base, a concentrated inorganic salt, an organic solvent or heat.
Molar conductivity is calculated using the formula Λm = κ/C, where κ is the conductivity and C is the molar concentration. Conductivity κ = 1/R * (l/A), where R is resistance, l is the distance between electrodes, and A is the area of the cross-section. Given R = 50 ohm, l = 2.0 cm, A = 4.0 cm², and C = 0.5 mol/L. First, calculate κ = (1/50) * (2/4) = 0.01 ohm⁻¹cm⁻¹. Then, convert the concentration to mol/cm³: C = 0.5 mol/L = 0.5 mol/1000 cm³ = 0.0005 mol/cm³. Finally, Λm = 0.01/0.0005 = 20 ohm⁻¹cm²mol⁻¹.
The salt bridge in an electrochemical cell maintains electrical neutrality by allowing ions to flow between the half-cells, preventing charge buildup that would stop the reaction.
[Cr(NH₃)₆]³⁺: Chromium is in +3 oxidation state, Cr³⁺ has a d³ configuration. NH₃ is a strong field ligand, causing pairing of electrons. The complex has an octahedral geometry with hybridization d²sp³. It is paramagnetic due to the presence of unpaired electrons.
Given: 4NH₃ + 5O₂ → 4NO + 6H₂O, and the rate of increase of NO is 0.18 mol in 50 sec. (i) Rate of reaction = (1/4) * (Δ[NO]/Δt) = (1/4) * (0.18/50) = 0.0009 mol/s. (ii) Rate of formation of H₂O = (6/4) * (Δ[NO]/Δt) = (6/4) * (0.18/50) = 0.0054 mol/s. (iii) Rate of disappearance of NH₃ = (Δ[NO]/Δt) = 0.18/50 = 0.0036 mol/s.
(i) Isopropyl chloride treated with alcoholic KOH undergoes dehydrohalogenation to form propene. (ii) Methyl bromide treated with sodium in dry ether undergoes Wurtz reaction to form ethane. (iii) Methyl chloride treated with KCN forms methyl cyanide (acetonitrile), which upon hydrolysis with dil. HCl gives acetic acid.
(a) Ethanol with HBr: C₂H₅OH + HBr → C₂H₅Br + H₂O Ethanol with HI: C₂H₅OH + HI → C₂H₅I + H₂O (b) Dehydration of alcohols to form alkenes is carried out with conc. H₂SO₄ because H₂SO₄ acts as a dehydrating agent and doesn't act as an oxidizing agent conc. HCl or HNO₃ might.

More Information

This is a collection of chemistry questions often seen in high school or early undergraduate studies covering a broad range of topics.

Tips

Pay attention to the specific conditions of each reaction, as they often dictate the product formed. When dealing with reaction rates, make sure to account for stoichiometry.