(a) Use average bond enthalpies (Table 8.3) to estimate H for the atomization of naphthalene, C10H8:

Verified step by step guidance

1. Identify the bonds present in naphthalene, C_{10}H_{8}. Naphthalene consists of carbon-carbon (C-C) single bonds, carbon-carbon (C=C) double bonds, and carbon-hydrogen (C-H) bonds.
2. Determine the number of each type of bond in a single molecule of naphthalene. Typically, naphthalene has 5 C-C single bonds, 6 C=C double bonds, and 8 C-H bonds.
3. Use the average bond enthalpies from Table 8.3 to find the energy required to break each type of bond. For example, use the bond enthalpy for C-C, C=C, and C-H bonds.
4. Calculate the total energy required to break all the bonds in one molecule of naphthalene by multiplying the number of each type of bond by its respective bond enthalpy and summing these values.
5. The total energy calculated represents the enthalpy change (\( \Delta H \)) for the atomization of naphthalene, as it is the energy required to break all bonds in the molecule.

Key Concepts

Bond Enthalpy

Bond enthalpy, or bond dissociation energy, is the energy required to break a specific bond in a molecule in the gas phase. It is an average value derived from various compounds and reflects the strength of a bond. Understanding bond enthalpy is crucial for estimating the energy changes during chemical reactions, such as atomization, where bonds are broken to form individual atoms.

Atomization

Atomization refers to the process of converting a compound into its individual atoms, typically requiring energy input to break all chemical bonds. In the context of naphthalene (C10H8), atomization involves breaking the carbon and hydrogen bonds to yield separate carbon and hydrogen atoms. The enthalpy change associated with this process can be calculated using the bond enthalpies of the bonds broken.

Enthalpy Change (ΔH)

Enthalpy change (ΔH) is a measure of the heat content change in a system during a chemical reaction at constant pressure. It can be calculated using the formula ΔH = Σ(bond enthalpies of bonds broken) - Σ(bond enthalpies of bonds formed). For the atomization of naphthalene, the total bond enthalpies of the bonds broken must be summed to estimate the overall energy change associated with the process.