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USING ENGLISH TO COMPARE THE ELEMENTS (resume 2)

Substances can be classified as solids, liquids, gases, or plasma. In addition, a fifth state of matter, the Bose-Einstein condensate has been discovered recently. However, it is not stable at normal earth conditions. Likewise, although plasma is the most abundant state of matter in the Universe, it is not common on the Earth under normal conditions, except for lightning. Most matter that students are familiar with will therefore be in a solid, liquid, or gaseous state.
An element is a pure substance that cannot be decomposed into simpler substances by normal chemical means. There are 109 different elements. Ninety of these are naturally occurring; the rest have been created in laboratories. Elements 110 and 118 are still being researched on. There will be more elements as technology can identify them. A symbol is used to represent the full name of an element. For example, H represents hydrogen; O represents oxygen, and Al represents aluminum. Sometimes the Latin name for an element is used as the basis for its symbol, for instance K represents potassium (kalium in Latin).

Three subatomic particles compose elements: protons, neutrons, and electrons. Protons, which have an electrical charge of +1, and neutrons, which have a neutral charge, make up the nucleus of an element. This nucleus is surrounded by a "cloud" of electrons, each of which as a charge of -1. The electrons spin around the nucleus in what are called orbits or shells. Each of the orbits can contain a set number of electrons. For instance, the first orbital from the nucleus has 2 electrons, the second has 8, the third has 8, the 4th has 16 and the fifth has 32, and so on. Each shell may not be full, depending on the number of electrons in the element, and the inner shells fill before the outer shells fill. Sodium, for example, has 11 electrons, which are located in the first, second, and third shells (2+8+1.)


" Priority elemental properties"
The nature of the elementality is the properties that change regularly in accordance with the increase of the atomic number of elements.
1. Atomic radius
    
The radius of the atom is the distance from the atomic nucleus to the electron shell outer.
    
* In one class from the top down the radius of the atom the greater it is.
    
* In one period from left to right, the radius of the atom the smaller 

Explanation:In one class from top to bottom, the atomic shell increases (remember the number of skins = the periodic number), so that the radius of atoms also grows larger.From left to right, the number of skins remains but the nuclear charge (atomic number) and the number of electrons in the skin increases. This results in a tug-of-war between the nucleus and the electron shell getting larger and smaller atomic radius.Table of Atomic radius Several Elements



2. Energy Ionization   

The ionisation energy is the minimum energy required to remove electrons from a neutral atom in a gas form. The energy required to release a second electron is called the ionization energy is the first ionisation energy. It can be concluded the periodic ionisation energy as follows. 
*In one class from top to bottom the ionization energy decreases      
*In one class from left to right ionisation energy tends to increase.  The tendency can be explained as follows:
From the top down in a group of radius of the atom increases so that the attraction of the nucleus to the outer electron is getting smaller. Electrons are increasingly easily released and the energy required to release smaller. From the left of the right in a period, the core attraction to the electron gets bigger so that the electrons are more difficult to remove. The energy needed to release the electrons is surely greater. The first Ionization energy table Elements in the Periodic Table of Elements (Kj / mol)


 
3. Electron Affinity    
Electron affinity is the amount of energy liberated by a neutral atom in the form of a gas at the time of receiving an electron to form a negative ion.
*In one class from the top down the affinity of the electron is getting smaller.
*In one period from left to child the greater the electron affinity. 
Explanation :    
If the negative ions formed are stable, the released energy is expressed by a negative sign (-). What if the negative ions formed are unstable, the energy required / absorbed is indicated by a positive sign (+). The tendency in electron affinities is more variable than ionization energies
Table Elastic Affinity Price Some Elements (Kj / mol)



Halogenic elements (Gol VIIA) have the greatest / most negative electron affinity that would most readily accept electrons. The tendency of electron affinity exhibits the same pattern with the ionization energy tendency pattern.


4. Electronegativity

Is a number that states the tendency of an element to attract electrons in a molecule of a compound.    *In one class from top down to electronegativity is diminishing
*
In a periodic from left to right to the electronegability of the elements.Explanation:

No specific properties can be measured to determine / compare the electronegativity of elements.    The ionisation energy and the electron affinity are related to the magnitude of the electrons' attraction. The greater the tensile force of electrons as large as the ionization energy, the larger (the more negative) the electron affinity. Thus, an element (eg Fluor) which has an ionization energy and a large electron affinity will  have a large electroegativity.
The greater the electronegativity, the element tends to more easily form a negative ion. The smaller the electronegativity, the element tends to be more difficult to form negative ions, and tend to more easily form positive ions.
Table Electronegativan Scale Elements in Elements Periodic Table.
 

Komentar

  1. Try to explain the meaning of ionization energy using simple and easy to understand language and examples!

    BalasHapus
    Balasan
    1. The ionisation energy (EI) is the energy required to move an outer electron from the atom in the gas state. EI is needed to overcome the attraction by the atom's nucleus which is positively charged to its outer electron. EI is affected by the effective nuclear charge and the arrangement of electrons in the valence shell. Generally a large effective nuclear charge results in electrons out of the atom being difficult so that a larger EI is required.

      Atom Na has no.atom 11, then its electron configuration is 2.8.1

      Then it can be written Na → Na + + e-
      Atoms of Na will lose electrons and excess one positive charge, or in other words Na atoms turn into Na + ions. Events occurring at these atoms are necessary for energy, due to changes in the position of electrons.

      Since all atoms except hydrogen have more than one electron, these atoms also have more than one ionisation energy. When the release involves the first electron, it is called the first EI, and if the second electron involved is called the second EI, and so on.

      Ionisation energy 1: Na (g) + E1 → Na + (g) + e-

      Ionisation energy 2: Na + (g) + E2 → Na2 + (g) + e-

      Hapus
  2. Try to compare alkaline and alkaline earth elements?

    BalasHapus
    Balasan
    1. Here are some differences of alkaline and alkaline earth
      * Alkaline earth metal is harder than alkaline because it has two valence electrons.
      * The density is higher, the melting point is higher.
      * Has a +2 oxidation number (compare free energy data for calcium metal reactions with acids producing Ca + and Ca2 +) although the second ionisation energy for alkaline earth ions is higher than the first.
      Water solubility is relatively more difficult, especially those with an oxidation-2 anion

      Hapus

  3. What the difference between oxygen and nitrogen?

    BalasHapus
    Balasan
    1. Oxygen or acid is a chemical element in a periodic table system that has the symbol O and atomic number 8. Oxygen can easily react with almost any other element (mainly to oxide). Oxygen is the third most abundant element in the universe based on the mass and the most abundant element in the Earth's crust. Diatomic oxygen gas fills 20.9% of the Earth's atmospheric volume.

      Whereas Nitrogen or limp is a chemical element in the periodic table that has the symbol N and atomic number 7. Nitrogen is very difficult to react with other elements or compounds. Named a limp because this substance is lazy, inactive reacts with other elements. Nitrogen fills 78.08% of Earth's atmosphere and is present in many living tissues.

      Hapus

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