Textbook Question
A common form of elemental phosphorus is the tetrahedral P4 molecule, where all four phosphorus atoms are equivalent:
(b) How many P-P bonds are there in the molecule?
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Ch.8 - Basic Concepts of Chemical Bonding
Brown15th EditionChemistry: The Central ScienceISBN: 9780137542970
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Table of contents
- Ch.1 - Introduction: Matter, Energy, and Measurement111
- Ch.2 - Atoms, Molecules, and Ions166
- Ch.3 - Chemical Reactions and Reaction Stoichiometry138
- Ch.4 - Reactions in Aqueous Solution127
- Ch.5 - Thermochemistry104
- Ch.6 - Electronic Structure of Atoms109
- Ch.7 - Periodic Properties of the Elements107
- Ch.8 - Basic Concepts of Chemical Bonding102
- Ch.9 - Molecular Geometry and Bonding Theories120
- Ch.10 - Gases122
- Ch.11 - Liquids and Intermolecular Forces79
- Ch.12 - Solids and Modern Materials102
- Ch.13 - Properties of Solutions99
- Ch.14 - Chemical Kinetics153
- Ch.15 - Chemical Equilibrium83
- Ch.16 - Acid-Base Equilibria109
- Ch.17 - Additional Aspects of Aqueous Equilibria117
- Ch.18 - Chemistry of the Environment60
- Ch.19 - Chemical Thermodynamics109
- Ch.20 - Electrochemistry113
- Ch.21 - Nuclear Chemistry79
- Ch.22 - Chemistry of the Nonmetals52
- Ch.23 - Transition Metals and Coordination Chemistry57
- Ch.24 - The Chemistry of Life: Organic and Biological Chemistry7
Brown15th EditionChemistry: The Central ScienceISBN: 9780137542970Not the one you use?Change textbook
Chapter 8, Problem 99d
Two compounds are isomers if they have the same chemical formula but different arrangements of atoms. Use Table 8.3 to estimate H for each of the following gas-phase isomerization reactions and indicate which isomer has the lower enthalpy. (d) Methyl isocyanide → Acetonitrile
Verified step by step guidance1
Identify the chemical formulas for methyl isocyanide and acetonitrile. Both compounds have the formula C2H3N.
Use Table 8.3 to find the standard enthalpy of formation (\( \Delta H_f^\circ \)) for each compound: methyl isocyanide and acetonitrile.
Calculate the enthalpy change (\( \Delta H \)) for the isomerization reaction using the formula: \( \Delta H = \Delta H_f^\circ (\text{products}) - \Delta H_f^\circ (\text{reactants}) \).
Substitute the \( \Delta H_f^\circ \) values from Table 8.3 into the equation to find \( \Delta H \) for the reaction: Methyl isocyanide → Acetonitrile.
Determine which isomer has the lower enthalpy by comparing the \( \Delta H_f^\circ \) values of methyl isocyanide and acetonitrile. The isomer with the lower \( \Delta H_f^\circ \) value is more stable.
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Isomerism
Isomerism refers to the phenomenon where two or more compounds share the same molecular formula but differ in the arrangement of atoms. This can lead to distinct physical and chemical properties, making isomers an important concept in organic chemistry. Isomers can be classified into structural isomers, which differ in connectivity, and stereoisomers, which differ in spatial arrangement.
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Guided course
2:14
Isomerism in Coordination Complexes Example
Enthalpy Change (ΔH)
Enthalpy change (ΔH) is a measure of the heat content of a system at constant pressure. It indicates whether a reaction is exothermic (releases heat, ΔH < 0) or endothermic (absorbs heat, ΔH > 0). In the context of isomerization reactions, comparing the enthalpy changes helps determine which isomer is more stable, as lower enthalpy corresponds to greater stability.
Gas-Phase Reactions
Gas-phase reactions occur when reactants and products are in the gaseous state, allowing for different kinetic and thermodynamic behaviors compared to reactions in solution or solid states. In gas-phase isomerization, factors such as molecular interactions and energy barriers play a crucial role in determining the reaction pathway and the stability of the resulting isomers.
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03:22Phase Changes in Diagrams
Related Practice
Textbook Question
Mothballs are composed of naphthalene, C10H8, a molecule that consists of two six-membered rings of carbon fused along an edge, as shown in this incomplete Lewis structure:
(c) Not all of the C—C bond lengths in naphthalene are equivalent. Based on your resonance structures, how many C—C bonds in the molecule do you expect to be shorter than the others?
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Textbook Question
A common form of elemental phosphorus is the tetrahedral P4 molecule, where all four phosphorus atoms are equivalent:
Draw a Lewis structure for a linear P4 molecule that satisfies the octet rule. Does this molecule have resonance structures?
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Textbook Question
Ortho-Dichlorobenzene, C6H4Cl2, is obtained when two of the adjacent hydrogen atoms in benzene are replaced with Cl atoms. A skeleton of the molecule is shown here. (b) Are there any resonance structures for the molecule? If so, sketch them.
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Textbook Question
Ortho-Dichlorobenzene, C6H4Cl2, is obtained when two of the adjacent hydrogen atoms in benzene are replaced with Cl atoms. A skeleton of the molecule is shown here. (a) Complete a Lewis structure for the molecule using bonds and electron pairs as needed.
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