Chemical Families 1 Periodic Table

The halogens are a family of elements appearing on the right side of the periodic table, in the column just before the inert gases. The elements in this group—fluorine, chlorine, bromine, iodine, and astatine—show some remarkable similarities and some interesting trends in chemical behavior. The similarities are expected since the... 

Silicon (Si) is a nonmetallic chemical element of the carbon family (Group rva of the periodic table) and makes up 27.7 percent of the Earth s crust. It is the second most abundant element in the crust, being surpassed only by oxygen. 

The periodic table is an extremely useful tabulation of the elements. It is constructed in a manner such that each vertical column contains elements which are chemically similar. The elements in the columns are called groups or families. (Elements in some of the groups arc very similar to each other. Elements in others of the groups are less similar. For example, the elements of the first group resemble each other more than the elements of the fourth group from the end, headed by N.) Each row in the table is called a period (Fig. 3-1). 

Hypervalency can be defined most simply with respect to purely empirical aspects of chemical periodicity. As beginning chemistry students are taught, each chemical family is associated with a column of the periodic table and associated valence atomic number ZAval, such that the empirical valency FAemp is the minimum shift of ZAval to reach the nearest rare gas,... 

However, Mendeleev received credit for devising the modern periodic table of the elements, even though his table was based on atomic mass numbers rather than the atomic proton numbers of the elements. In 1871 he arranged the elements not only by their atomic mass in horizontal rows (periods), but also in vertical columns (groups, also called families) by their valences as well as other chemical and physical characteristics. 

The halogens are the family of nonmetal elements in group 17 (VIIA) that are located just to the right of the oxygen group 16 on the periodic table of chemical elements. They are fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At). 

Tellurium is the fourth element of the VIA family of the periodic table, which starts with oxygen. Since tellurium exhibits an electronic configuration similar to that of selenium and sulphur, the chemical behaviour of these elements is obviously closely related. This similarity was a hindrance to the greater development of tellurium chemistry. During several decades, research was restricted to an extrapolation of well-established reactions for the preparation and use of organic sulphur compounds to selenium, and mainly from selenium to tellurium. 

Chemical Family a group of elements that share similar chemical properties and share the same column in the periodic table, for example, halogens, alkali earth Chirality condition that describes the handedness of a molecule or whether a molecule exists in forms that can be superimposed on each other Chlorofluorocarbons also called CFCs, compounds consisting of chorine, fluorine, and carbon that are responsible for stratospheric ozone destruction Coagulation precipitation or separation from a dispersed state Coefficient of Thermal Expansion measure of the rate at which a substance will expand when heated... 

Isotopes are thus a kind of free give-away bonus to the Periodic Table. In a sense they expand our choice of elements by giving us extra versions that do unique and useful things. We do well to remember that each entry in the table represents not a sole member of the element family but a kind of averaged image of a small group of chemical brothers and sisters, each with their own talents. 

Research the common physical and chemical properties for each family (a vertical column) in the periodic table. The families to consider are alkali metals, alkaline earth metals, inert gases, halogens, and transition metals. 

A family is a vertical column of elements on the periodic table that contains elements with similar chemical properties, physical properties, and electron configurations. 

A column of the periodic table is called a family. Some families have special names. Group IA elements are called alkali metals, group IIA elements are called alkaline earth metals, group VIIA elements are called halogens, and group VIIIA elements are called the noble gases. The group B elements are called transition elements. Elements with atomic numbers from 58 to 71 are called lanthanides, and elements with atomic numbers from 90 to 103 are called actinides. Families have similar chemical and physical properties. For example, the alkali metals are soft metals at room temperature they are shiny, conduct... 

Consider making a mobile three-dimensional periodic table. (See Activity 5.6, p. 225.) Remember that families and rows must be kept intact. To construct a balanced mobile, it is easier to start at the lowest section. Add periodic table sections and balance the section. Then work toward the top. Make the periodic table mobile useful. An observer should be able to locate an element and know its physical and chemical properties. 

Which families of the periodic table have the most chemically active metals Which are least reactive Explain your answer. 

As we move down the family of alkali metals on the periodic table, metal chemical reactivity increases. This increase in reactivity corresponds to an increase in atomic size. As atomic size increases, the outermost electrons are farther from the atomic nucleus. The positively charged protons in the atomic nucleus are trying to attract the negatively charged outermost electrons, but attractive force decreases as distance increases. This is analogous to a mother trying to keep her children home while the children, as they become more energetic, wander farther away and often eventually leave home. A child can leave home more easily when already distanced from home. Therefore, cesium (Cs), in which the outermost electron is far from the positive nucleus and can easily leave home, is much more chemically reactive than lithium (Li), in which the outermost electron is close to home, the nucleus. 

Periodic table An arrangement of the chemical elements in order of their atomic numbers. Arranged as horizontal periods and vertical groups or families of elements with similar properties. Its initiation is attributed to the nineteenth century Russian chemist Mendeleyev. A modem periodic table, which differs significantly from early ones, is shown on page 283. 

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