main group element

Examples of main group element in the following topics:

• The Expanded Octet

  • Main group elements in the third period and below form compounds that deviate from the octet rule by having more than 8 valence electrons.
  • A hypervalent molecule is a molecule that contains one or more main group elements that bear more than eight electrons in their valence levels as a result of bonding.
  • For the elements in the second period of the periodic table (principal energy level n=2), the s2p6 electrons comprise the octet, and no d sublevel exists.
  • As a result, the second period elements (more specifically, the nonmetals C, N, O, F) obey the octet rule without exceptions.
  • However, some of the third-period elements (Si, P, S, and Cl) have been observed to bond to more than four other atoms, and thus need to involve more than the four pairs of electrons available in an s2p6 octet.

• The Periodic Table

  • Devised by Russian chemist Dmitri Mendeleev (1834–1907) in 1869, the table groups elements that, although unique, share certain chemical properties with other elements.
  • In the periodic table the elements are organized and displayed according to their atomic number and are arranged in a series of rows (periods) and columns (groups) based on shared chemical and physical properties.
  • The arrangement of the periodic table allows the elements to be grouped according to their chemical properties.
  • Within the main group elements ( Groups 1-2, 13-18), there are some general trends that we can observe.
  • The further down a given group, the elements have an increased metallic character: they are good conductors of both heat and electricity, solids at room temperature, and shiny in appearance.

• Oxidation Numbers of Metals in Coordination Compounds

  • Transition metals are the elements in Groups 3 to 12 representing the d block of the periodic table.
  • The oxidation number is placed in parentheses after the name of the element (iron(III)).
  • However, it decreases in the latter elements.
  • Main-group elements, those in Groups 13 to 17, also exhibit multiple oxidation states.
  • The "common" oxidation states of these elements typically differ by two.

• Lanthanides and Actinides

  • The lanthanides and actinides form a group that appears almost disconnected from the rest of the periodic table.
  • This is due to the proper numerical position between Groups 2 and 3 of the transition metals.
  • The 14 elements (numbers 58 to 71) of the lanthanide series are also known as the rare earth elements.
  • The chemistry of the lanthanides differs from main group elements and transition metals because of the nature of the 4f orbitals.
  • The red highlighted group shows the lanthanide series and the blue highlighted group shows the actinide series.

• Variation of Physical Properties Within a Group

  • The physical properties (notably, melting and boiling points) of the elements in a given group vary as you move down the table.
  • In chemistry, a group is a vertical column in the periodic table of the chemical elements.
  • There are 18 groups in the standard periodic table, including the d-block elements but excluding the f-block elements.
  • Within a group of the periodic table, each element has the same valence electron configuration.
  • In the main group elements, the boron and carbon families (Groups 13 and 14) decrease in their boiling and melting points as you move down the group, whereas the nitrogen, oxygen, and fluorine families (Groups 15, 16, and 17) tend to increase in both.

• Electron Configurations and Magnetic Properties of Ions

  • The periodic table does more than just list the elements.
  • These elements comprise the s block of the periodic table.
  • The s and p blocks make up the main-group elements, also known as representative elements.
  • Elements in the same group or family have the same configuration of valence electrons, so they behave in chemically similar ways.
  • The magnetic properties of a given element depend on the electron configuration of that element, which will change when the element loses or gains an electron to form an ion.

• The Periodic Table

  • The standard form of the table comprises an eighteen by seven grid or main body of elements, positioned above a smaller double row of elements.
  • The columns of the s-, d-, and p-blocks are called groups, some of which have names such as the halogens or the noble gases.
  • They are always grouped together under a single element.
  • The production of elements beyond ununoctium is being pursued.
  • Mendeleev's 1869 periodic table presents the periods vertically and the groups horizontally.

• General Trends in Chemical Properties

  • The main body of the table is an 18 by 7 grid, and elements with the same number of valence electrons are kept together in groups (columns), such as the halogens and the noble gases.
  • The f block is usually included below the main table rather than within it to minimize the table's width.
  • Elements in the same group show patterns in atomic radius, ionization energy, and electronegativity.
  • From top to bottom in a group, the atomic radii of the elements increase: since there are more filled energy levels, valence electrons are found farther from the nucleus.
  • The number of valence shell electrons determines the family, or group, to which the element belongs.

• Periodic Table Position and Electron Configuration

  • The main body of the table is a 18 × 7 grid.
  • Elements with the same number of valence electrons are kept together in groups, such as the halogens and the noble gases.
  • The f-block is usually not included in the main table, but rather is floated below, as an inline f-block would often make the table impractically wide.
  • The elements in this table are laid out in the standard configuration of periods and groups.
  • Use the periodic table to identify atom properties such as groups and electron configurations.

• Rhythm

  • They are often called the basic elements of music.
  • The main purpose of music theory is to describe various pieces of music in terms of their similarities and differences in these elements, and music is usually grouped into genres based on similarities in all or most elements.
  • So perhaps the other three elements can be considered the most basic components of music.
  • It can also refer to the pattern in time of a single small group of notes (as in "play this rhythm for me").
  • Measure or bar - Beats are grouped into measures or bars.