Classify elementsMake predictions about the periodicity nature of the representative elements

We start this ar by assessing the habits of representative metals in relationship to your positions in the periodic table. The primary emphasis of this section will it is in the application of periodicity to the representative metals.

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It is feasible to divide facets into teams according to their electron configurations. The representative elements are facets where the s and also p orbitals space filling. The transition elements are facets where the d orbitals (groups 3–11 top top the regular table) space filling, and the inner change metals are the aspects where the f orbitals are filling. The d orbitals fill through the aspects in team 11; therefore, the aspects in group 12 qualify together representative aspects because the critical electron enters an s orbital. Metals among the representative aspects are the representative metals. Metallic character results from an element’s ability to lose its outer valence electrons and also results in high thermal and electrical conductivity, amongst other physical and chemical properties. There room 20 nonradioactive representative metals in teams 1, 2, 3, 12, 13, 14, and also 15 of the routine table (the aspects shaded in yellow in figure 1). The radioactive elements copernicium, flerovium, polonium, and also livermorium are additionally metals however are past the border of this chapter.

In addition to the representative metals, several of the representative aspects are metalloids. A metalloid is an element that has actually properties the are between those that metals and also nonmetals; these aspects are commonly semiconductors.

The remaining representative aspects are nonmetals. Uneven metals, i beg your pardon typically type cations and ionic link (containing ionic bonds), nonmetals tend to type anions or molecule compounds. In general, the mix of a metal and also a nonmetal produces a salt. A salt is one ionic compound consisting of cations and anions.


Figure 3. To prevent call with air and also water, potassium for laboratory use comes together sticks or beads save under kerosene or mineral oil, or in sealed containers. (credit:


Figure 5. From left to right: Mg(s), warm water at pH 7, and also the resulting solution with a pH greater than 7, as suggested by the pink color of the phenolphthalein indicator. (credit: change of occupational by Sahar Atwa)

The potent reducing strength of hot magnesium is useful in prepare some steels from your oxides. Indeed, magnesium’s affinity because that oxygen is so good that burning magnesium reacts through carbon dioxide, developing elemental carbon:


For this reason, a CO2 fire extinguisher will not extinguish a magnesium fire. Additionally, the excellent white light emitted by burning magnesium provides it beneficial in flares and fireworks.

Group 12


Figure 7. Indigenous left to right: Hg(l), Hg+ focused HCl, Hg+ focused HNO3. (credit: Sahar Atwa)

Most mercury compound decompose when heated. Most mercury compounds save mercury with a 2+-oxidation state. As soon as there is a large excess of mercury, that is possible to kind compounds containing the \textHg_2^2+ ion. All mercury compounds are toxic, and also it is necessary to exercise great care in their synthesis.


An amalgam is an alloy of mercury through one or more other metals. This is comparable to considering stole to it is in an alloy of iron with other metals. Most metals will type an amalgam v mercury, v the key exceptions being iron, platinum, tungsten, and also tantalum.

Due come toxicity problems with mercury, there has been a far-reaching decrease in the usage of amalgams. Historically, amalgams were vital in electrolytic cells and also in the extraction of gold. Amalgams that the alkali metals still discover use since they are strong reducing agents and also easier to manage than the pure alkali metals.

Prospectors had actually a problem when lock found carefully divided gold. Lock learned that including mercury to their pans collected the gold into the mercury to kind an amalgam for simpler collection. Unfortunately, accident of tiny amounts that mercury end the years left many streams in California polluted v mercury.

Dentists use amalgams comprise silver and also other steels to to fill cavities. There space several reasons to usage an amalgam including low cost, lull of manipulation, and longevity compared to alternative materials. Dental amalgams are approximately 50% mercury through weight, which, in recent years, has become a problem due to the toxicity that mercury.

After reviewing the best available data, the Food and also Drug administration (FDA) considers amalgam-based fillings to be safe for adults and also children over 6 years that age. Also with many fillings, the mercury level in the patients stay far listed below the shortest levels associated with harm. Clinical researches have found no link between dental amalgams and also health problems. Health concerns may no be the same in situations of children under 6 or pregnant women. The FDA conclusions room in line v the opinions of the eco-friendly Protection firm (EPA) and also Centers for an illness Control (CDC). The only health and wellness consideration listed is that some civilization are allergy to the amalgam or among its components.

Group 13

Group 13 contains the metalloid boron and also the steels aluminum, gallium, indium, and thallium. The lightest element, boron, is semiconducting, and also its binary compounds tend to be covalent and also not ionic. The remaining facets of the team are metals, however their oxides and hydroxides readjust characters. The oxides and hydroxides the aluminum and also gallium exhibit both acidic and straightforward behaviors. A substance, such as these two, that will certainly react v both acids and also bases is amphoteric. This characteristic illustrates the combination of nonmetallic and also metallic behaviors of these 2 elements. Indium and thallium oxides and hydroxides exhibit only simple behavior, in accordance v the clearly metallic personality of these two elements. The melting point of gallium is unusually low (about 30 °C) and will melt in her hand.

Aluminum is amphoteric since it will react v both acids and bases. A usual reaction through an acid is:


The assets of the reaction the aluminum v a base depend upon the reaction conditions, v the adhering to being one possibility:


With both acids and also bases, the reaction v aluminum generates hydrogen gas.

The group 13 facets have a valence covering electron construction of ns2np1. Aluminum generally uses every one of its valence electrons once it reacts, offering compounds in i m sorry it has an oxidation state the 3+. Although countless of this compounds space covalent, others, such as AlF3 and also Al2(SO4)3, room ionic. Aqueous solutions of aluminum salts contain the cation \left<\textAl\left(\textH_2\textO\right)_6\right>^3+, abbreviated as Al3+(aq). Gallium, indium, and also thallium also type ionic compounds containing M3+ ions. These three facets exhibit not just the meant oxidation state that 3+ native the 3 valence electrons but additionally an oxidation state (in this case, 1+) the is two listed below the supposed value. This phenomenon, the inert pair effect, refers to the formation of a stable ion with an oxidation state two lower than supposed for the group. The pair of electron is the valence s orbital because that those elements. In general, the inert pair result is crucial for the reduced p-block elements. In an aqueous solution, the Tl+(aq) ion is more stable 보다 is Tl3+(aq). In general, these steels will react with air and also water to type 3+ ions; however, thallium reacts to provide thallium(I) derivatives. The steels of group 13 all react directly with nonmetals such together sulfur, phosphorus, and also the halogens, forming binary compounds.

The steels of team 13 (Al, Ga, In, and Tl) room all reactive. However, passivation occurs together a tough, hard, thin film that the metal oxide forms upon exposure to air. Disruption the this movie may respond to the passivation, enabling the steel to react. One way to disrupt the film is to disclose the passivated metal to mercury. Few of the steel dissolves in the mercury to type an amalgam, i m sorry sheds the protective oxide great to disclose the metal to additional reaction. The formation of an amalgam allows the steel to react through air and water.

Although easily oxidized, the passivation that aluminum provides it an extremely useful as a strong, lightweight building material. Because of the formation of one amalgam, mercury is corrosive to structural products made the aluminum. This video clip demonstrates exactly how the verity of one aluminum beam have the right to be destroyed by the enhancement of a tiny amount of elemental mercury.

The most crucial uses the aluminum space in the construction and transportation industries, and also in the to produce of aluminum cans and also aluminum foil. These provides depend on the lightness, toughness, and strength that the metal, and its resistance come corrosion. Due to the fact that aluminum is wonderful conductor that heat and resists corrosion, that is helpful in the produce of cooking utensils.

Aluminum is a very great reducing agent and also may replace other reducing agents in the isolation of specific metals from your oxides. Although more expensive 보다 reduction by carbon, aluminum is crucial in the isolation the Mo, W, and Cr from your oxides.

Group 14

The metallic members of group 14 are tin, lead, and flerovium. Carbon is a typical nonmetal. The remaining aspects of the group, silicon and also germanium, are instances of semimetals or metalloids. Tin and lead type the secure divalent cations, Sn2+ and also Pb2+, through oxidation claims two below the group oxidation state the 4+. The stability of this oxidation state is a repercussion of the inert pair effect. Tin and lead also kind covalent compounds v a formal 4+-oxidation state. For example, SnCl4 and also PbCl4 room low-boiling covalent liquids.


Figure 8. (a) Tin(II) chloride is one ionic solid; (b) tin(IV) chloride is a covalent liquid.

Tin reacts readily with nonmetals and also acids to kind tin(II) compound (indicating the it is an ext easily oxidized than hydrogen) and with nonmetals to form either tin(II) or tin(IV) compound (shown in number 8), depending upon the stoichiometry and also reaction conditions. Lead is less reactive. The is just slightly simpler to oxidize than hydrogen, and oxidation generally requires a hot focused acid.

Many of these facets exist together allotropes. Allotropes room two or an ext forms that the same facet in the exact same physical state with different chemical and also physical properties. There space two usual allotropes of tin. This allotropes space grey (brittle) tin and white tin. As with other allotropes, the difference in between these develops of believe is in the arrangement of the atoms. White believe is stable above 13.2 °C and is malleable like various other metals. At short temperatures, gray tin is the an ext stable form. Gray tin is brittle and tends to failure to a powder. Consequently, articles made the tin will certainly disintegrate in cold weather, an especially if the cold order is lengthy. The readjust progresses slowly from the spot of origin, and the gray tin the is very first formed catalyzes further change. In a way, this impact is comparable to the spread out of an epidemic in a tree or animal body, leading people to speak to this process tin an illness or believe pest.

The primary use of tin is in the coating of steel to form tin plate-sheet iron, which constitutes the tin in believe cans. Essential tin alloys are bronze (Cu and also Sn) and also solder (Sn and also Pb). Lead is important in the command storage battery in automobiles.

Group 15

Bismuth, the most heavy member of team 15, is a much less reactive metal than the other representative metals. That readily provides up three of its five valence electrons to active nonmetals to kind the tri-positive ion, Bi3+. It creates compounds v the group oxidation state that 5+ only as soon as treated with strong oxidizing agents. The stability of the 3+-oxidation state is an additional example that the inert pair effect.

Key Concepts and Summary

This section concentrates on the periodicity of the representative elements. These are the facets where the electrons are entering the s and also p orbitals. The representative elements occur in teams 1, 2, and 12–18. These facets are representative metals, metalloids, and nonmetals. The alkali metals (group 1) are very reactive, readily type ions v a fee of 1+ to type ionic link that space usually dissolve in water, and react vigorously v water to form hydrogen gas and a basic solution the the metal hydroxide. The outermost electron of the alkaline earth metals (group 2) are more difficult to remove than the external electron of the alkali metals, bring about the group 2 metals being less reactive than those in team 1. These facets easily type compounds in i m sorry the steels exhibit one oxidation state the 2+. Zinc, cadmium, and also mercury (group 12) generally exhibit the team oxidation state of 2+ (although mercury likewise exhibits one oxidation state that 1+ in compounds that contain \textHg_2^2+ ). Aluminum, gallium, indium, and also thallium (group 13) are less complicated to oxidize than is hydrogen. Aluminum, gallium, and also indium happen with an oxidation state 3+ (however, thallium additionally commonly occurs together the Tl+ ion). Tin and lead form stable divalent cations and covalent compound in which the steels exhibit the 4+-oxidation state.

How carry out alkali metals differ native alkaline planet metals in atom structure and general properties?Why walk the reactivity that the alkali steels decrease native cesium come lithium?Predict the formulas because that the ripe compounds the may form when each species in shaft 1 the the table below reacts v each species in shaft 2.12
Predict the best an option in every of the following. You might wish to evaluation the thing on electronic structure for pertinent examples.the many metallic the the aspects Al, Be, and also Bathe most covalent that the compound NaCl, CaCl2, and also BeCl2the lowest an initial ionization energy among the elements Rb, K, and Lithe smallest amongst Al, Al+, and Al3+the largest amongst Cs+, Ba2+, and also XeSodium chloride and also strontium chloride space both white solids. How could you differentiate one from the other?The reaction of quicklime, CaO, v water produces slaked lime, Ca(OH)2, i beg your pardon is widely provided in the building and construction industry to do mortar and also plaster. The reaction that quicklime and water is very exothermic:\textCaO\left(s\right)+\textH_2\textO\left(l\right)\rightarrow\textCa\left(\textOH\right)_2\left(s\right)\Delta H=\text-350 kJ\textmol^\text-1What is the enthalpy that reaction per gram the quicklime the reacts?How much heat, in kilojoules, is linked with the manufacturing of 1 ton that slaked lime?Write a well balanced equation for the reaction of elemental strontium with each of the following:oxygenhydrogen bromidehydrogenphosphoruswaterHow numerous moles of ionic varieties are current in 1.0 l of a solution significant 1.0 M mercury(I) nitrate?What is the massive of fish, in kilograms, that one would have to consume to acquire a fatal sheep of mercury, if the fish has 30 parts per million that mercury by weight? (Assume the all the mercury indigenous the fish ends up together mercury(II) chloride in the body and that a fatal dose is 0.20 g that HgCl2.) How plenty of pounds the fish is this?The elements sodium, aluminum, and chlorine are in the same period.Which has the biggest electronegativity?Which the the atom is smallest?Write the Lewis framework for the simplest covalent compound that can form between aluminum and also chlorine.Will the oxide the each aspect be acidic, basic, or amphoteric?Does metallic believe react through HCl?What is tin pest, additionally known together tin disease?Compare the nature of the binding in PbCl2 to the of the bond in PbCl4.Is the reaction the rubidium with water more or much less vigorous 보다 that of sodium? just how does the price of reaction that magnesium compare?
Selected Answers

1. The alkali steels all have actually a solitary s electron in their outermost shell. In contrast, the alkaline planet metals have actually a perfect s subshell in their outermost shell. In general, the alkali steels react faster and also are more reactive 보다 the matching alkaline earth metals in the same period.

3. \beginarrayl\textNa+\textI_2\rightarrow\text2NaI\\ \text2Na+\textSe\rightarrow\textNa_2\textSe\\ \text2Na+\textO_2\rightarrow\textNa_2\textO_2\endarray

\beginarrayl\textSr+\textI_2\rightarrow\textSrI_2\\ \textSr+\textSe\rightarrow\textSeSe\\ \text2Sr+\textO_2\rightarrow\text2SrO\endarray

\beginarrayl\text2Al+\text3I_2\rightarrow\text2AlI_3\\ \text2Al+\text3Se\rightarrow\textAl_2\textSe_3\\ \text4Al+\text3O_2\rightarrow\text2Al_2\textO_3\endarray

5. The feasible ways that distinguishing between the two include infrared spectroscopy by comparison of well-known compounds, a flame test that gives the characteristic yellow color for salt (strontium has actually a red flame), or comparison of your solubilities in water. At 20 °C, NaCl dissolves to the degree of \frac\text35.7 g\text100 mL contrasted with \frac\text53.8 g\text100 mL for SrCl2. Heater to 100 \textdegree C provides basic test, because the solubility the NaCl is \frac\text39.12 g\text100 mL, but that of SrCl2 is \frac\text100.8 g\text100 mL. density determination top top a hard is occasionally difficult, but there is enough difference (2.165 g/mL NaCl and also 3.052 g/mL SrCl2) the this technique would be viable and perhaps the easiest and least expensive check to perform.

7. (a) \text2Sr\left(s\right)+\textO_2\left(g\right)\rightarrow\text2SrO\left(s\right)

(b) \textSr\left(s\right)+\text2HBr\left(g\right)\rightarrow\textSrBr_2\left(s\right)+\textH_2\left(g\right)

(c) \textSr\left(s\right)+\textH_2\left(g\right)\rightarrow\textSrH_2\left(s\right)

(d) \text6Sr\left(s\right)+\textP_4\left(s\right)\rightarrow\text2Sr_3\textP_2\left(s\right)

(e) \textSr\left(s\right)+\text2H_2\textO\left(l\right)\rightarrow\textSr\left(\textOH\right)_2\left(aq\right)+\textH_2\left(g\right)

9. The mass of Hg in 0.20 g HgCl2 is 0.20\cancel\textg HgCl_2\times \frac\text200.59 g Hg271.50\cancel\textg HgCl_2=\text0.15 g Hg.

Then \frac301\times 10^6\times \textmass that fish=\text0.15 g Hg. massive of fish = 5.0 × 103 g. To convert to systems of pounds, 5.0\times 10^3\cancel\textg\times \frac\text1 lb453.6\cancel\textg=\text11 lb

11. Yes, believe reacts v hydrochloric mountain to produce hydrogen gas. This ability can be established from the typical reduction potentials in traditional Electrode (Half-Cell) Potentials.

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13. In PbCl2, the bonding is ionic, as indicated by its melting point of 501 °C. In PbCl4, the bonding is covalent, as shown by it gift an rough liquid at room temperature.


alkaline planet metalany of the metals (beryllium, magnesium, calcium, strontium, barium, and also radium) occupying group 2 that the periodic table; they are reactive, divalent steels that kind basic oxides

allotropestwo or more forms of the very same element, in the very same physical state, with different chemical structures

bismuthheaviest member of group 15; a less reactive steel than various other representative metals

metalatoms the the metallic elements of teams 1, 2, 12, 13, 14, 15, and 16, which type ionic link by shedding electrons indigenous their external s or p orbitals

metalloidelement that has actually properties the are in between those of metals and nonmetals; these aspects are generally semiconductors

passivationmetals through a protective nonreactive movie of oxide or various other compound the creates a obstacle for chemistry reactions; physical or chemistry removal the the passivating film permits the steels to demonstrate their meant chemical reactivity