Standard enthalpy of atomization

The so-called Laidler scheme was developed as a tool to estimate standard enthalpies of formation of organic compounds [90], It relies on the bond-additivity concept, that is, it assumes that the standard enthalpy of atomization of a given molecule in the gas phase (Aat//°, defined as the standard enthalpy of the reaction where all the chemical bonds are cleaved, yielding the gaseous ground-state atoms) can be evaluated by adding the relevant bond enthalpy terms. For instance, in the case of phenol, its standard enthalpy of atomization, or simply its enthalpy of atomization, refers to reaction 5.28 at 298.15 K ... 

Element Standard enthalpy of atomization/ kJ mol-1 Standard enthalpy of formation of EFg/kJ mob1... 

Melting and boiling points and standard enthalpies of atomization of the metallic elements... 

Table 4.3.4. Melting points [mp(K), upper], boiling points [bp(K), middle], and standard enthalpies of atomization [AH°t (kJ mol-1), bottom] of metallic elements...

Fig. 1. Standard enthalpies of atomization for elements of the three series.

The standard enthalpy of atomization of an element is the energy required to convert one mole of an element in its most stable form at 25°C to one mole of monatomic gas. Given that the standard enthalpy of atomization for sodium is 108.4 kJ/mol, calculate the energy in kilojoules required to convert one mole of sodium metal at 25°C to one mole of gaseous Na ions. 

Table 5.2 Structures (at 298 K), melting points (K) and values of the standard enthalpies of atomization of the metallic elements. = hep = ccp (fee) = bcc...

Values of the standard enthalpies of atomization, Aj,7/"(298 K), (or sublimation) in Table 5.2 refer to the processes defined in equation 5.2, and correspond to the destruction of the metallic lattice. Mercury is an exception, since at 298 K it is a liquid. 

Refer to Table 5.2. (a) Write an equation for the process for which the standard enthalpy of atomization of cobalt is defined, (b) Suggest reasons for the trend in standard enthalpies of atomization on descending group 1. (c) Outline possible reasons for the trend in values of Aa//° on going from Cs to Bi. 

Construct an appropriate Hess cycle, bearing in mind that the P—H bond enthalpy term can be determined from the standard enthalpy of atomization of PH3(g). 

Standard enthalpies of atomization of the elements are listed in Appendix 10. 

Fig. 19.2 Trends in standard enthalpies of atomization, A H°(29S K), across the three rows of s- and d-block metals K to Zn,...

Fig. 22.2 Trends in the values of standard enthalpies of atomization (298 K) of the <5 -block metals values are given in Tables 21.1 and 22.2.

The standard enthalpy of atomization of aluminium is 326kJmol . Calculate the enthalpy change for the process AI(s) AP+(g) + 3e-... 

Standard enthalpy of atomization (kJ moP ) Metallic radius for 12-coordinate atom (pm)... 

Table 25.4 Standard enthalpies of atomization and hydration (at 298 K) of the Ln ions, sums of the first three ionization energies of Ln(g), and standard reduction potentials for the lanthanoid metal ions.

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