Boiling points of the halogens

Using the data from Table 19-11, plot on one set of axes the melting and boiling points of the halogens versus row number. 

Self-Test 15.5B Explain the trends in the melting points and boiling points of the halogens. 

Boiling points of the halogens increase with the number of electrons. 

Boron, which occurs in the second period of the periodic system as a tervalent ion, is naturally very small (see Table F), and, in the compounds which it forms with the halogens, the boron ion will be completely shielded by the three halogen ions, so that the boron halides are thus compounds with low boiling points. Of the halogen ions, iodine, which contains the most electrons, is the largest. In aluminium iodide the three iodine ions will shield the aluminium ion, as also do the somewhat smaller bromine or chlorine ions in... 

The compounds are separated on the GC column, temperature programmed, and determined by an ECD, FID, or MS. Although these methods were developed for a limited number of specific compounds, the same methods may be applied to related compounds. Selection of the methods should be based on the boiling points of the halogenated hydrocarbons. Table 2.9.4 presents U.S. EPA s Method numbers for air analysis of halogenated hydrocarbons. Analysis of compounds not listed in Table 2.9.4, however, may be performed by similar procedures, based on their boiling points. 

Why is the boiling point of the halogen In each period greater than the noble gas ... 

A Figure 11.5 Boiling points of the halogens and noble gases. This plot shows how the boiling points Increase due to stronger dispersion forces as the molecular weight Increases. 

TABLE 11.3 Boiling Points of the Halogens and the Noble Cases ... 

Table 4.13 shows the boiling points of the halogens. The molecules increase in size and contain a greater number of electrons as group 17 is descended. In addition, the electrons become located... 

---