S block elements

The usefulness of the main-group elements in materials is related to their properties, which can be predicted from periodic trends. For example, an s-block element has a low ionization energy, which means that its outermost electrons can easily be lost. An s-block element is therefore likely to be a reactive metal with all the characteristics that the name metal implies (Table 1.4, Fig. 1.60). Because ionization energies are... 

Hydrogen sulfide dissolves in water to give a solution of hydrosulfuric acid that, as a result of its oxidation by dissolved air, slowly becomes cloudy as S8 molecules form and then coagulate. Hydrosulfuric acid is a weak diprotic acid and the parent acid of the hydrogen sulfides (which contain the HS ion) and the sulfides (which contain the S2 ion). The sulfides of the s-block elements are moderately soluble, whereas the sulfides of the heavy p- and d-block metals are generally very insoluble. 

Beryllium behaves differently from the other s-block elements because the fi = 2 orbitals are more compact than orbitals with higher principal quantum number. The first ionization energy of beryllium, 899 kJ/mol, is comparable with those of nonmetals, so beryllium does not form compounds that are clearly ionic. 

Some compounds of the s-block elements are important industrial chemicals, too. For example, more than 1.4 billion kilograms of K2 CO3 (potassium carbonate, whose common name is potash), is produced in the United States each year. This compound, which is obtained from mineral deposits, is the most common source of potassium for fertilizers. Fertilization with potassium is necessary because this element is essential for healthy plant growth. Moreover, potassium salts are highly soluble in water, so potassium quickly becomes depleted from the soil. Consequently, agricultural land requires frequent addition of potassium fertilizers. 

Three other compounds of s-block elements—calcium oxide (CaO, known as lime ), sodium hydroxide (NaOH), and sodium carbonate (Na2 CO3)—are among the top 15 industrial chemicals in annual production. Lime is perennially in the top 10 because it is the key ingredient in construction materials such as concrete, cement, mortar, and plaster. Two other compounds, calcium chloride (CaCl2 ) and sodium sulfate (Na2 SO4 ), rank just below the top 50 in industrial importance. 

C08-0026. Consult the table of first ionization energies in Appendix C and calculate the average values for the nonmetals, metalloids, and s-block elements. How does the trend in these averages relate to the ionic chemistry of these elements ... 

The aim of this chapter is to review the chemistry of chalcogenolates in the last 10 years. The more recent reviews in this field included chalcogenolates of the s-block elements,13,14 early transition metal thiolates,15 metal complexes with selenolate and tellurolate ligands,16 copper(I), lithium and magnesium thiolates,17 functionalized thiolate complexes,18 19 pentafluorobenzenethiolate platinum group compounds,20 tellurium derivatives,21 luminescent gold compounds,22 and complexes with lanthanide or actinide.23... 

All elements in group 2 (IIA) have electron configurations that end with the notation s. The link between n value and period number is correctly applied. Strontium has an electron configuration with the general notation ns, which is characteristic of s block elements. 

Redox electrodes. The majority of redox electrodes are transition metals, although some p-block elements such as tin and lead and s-block elements such as... 

It has been proposed that the ability of a cation to polarize anions is proportional to its charge divided by its radius (see Section 2.15). (a) Use this criterion to arrange the s-block elements in order of increasing polarizing power, (b) Do the resulting values support the diagonal relationships within the block ... 

They are subdivided into the s-block elements of groups 1A and 2 A, with valence electron configuration ns1 or ns2, and the p-block elements of groups 3A-8A, with valence configurations... 

Look at the electron configurations of potassium and calcium, the s-block elements immediately preceding the first transition series. These atoms have 4s valence electrons, but no d electrons ... 

For each block (s-, p-, A-), the first series involved has somewhat distinct chemistry compared with subsequent ones. Hydrogen is different from other s-block elements, the 2p-series (B-F) is different from others, 3d-series is different from 4d and 5d-series, etc. 

Reactivity Nitrogen is present as N2 (N0 N) and is very inert at ordinary temperatures and does not react with many metals directly. However at higher temperatures it reacts with s block elements. For example it forms magnesium and lithium nitrides when they are heated in it. 

Since their isolation in 1991,1 N-heterocyclic carbenes (NHCs) have become ubiquitous in organometallic chemistry. In more recent years investigations into the coordination of NHCs to other elements have expanded, and there are examples of their coordination to elements across the whole periodic table. This report gives an overview of NHC complexes of non-transition metal elements, ranging from the s-block elements, through the p-block and on to the lanthanides. 

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