Using english to Compare the element

The Elemennt

Any element or compound contained in the sea or in air has distinctive properties that are different from other elements or compounds. Trends that occur due to the physical and chemical properties between elements in a group or period table

1. Understanding the elements

The element is a single substance that can not be decomposed into other substances simpler through ordinary chemical reactions. The smallest part of an element is an atom. Some examples of elements are gold, silver, aluminum, copper, sulfur, carbon, and so on. Up to now has been known for more than 112 elements, was found in a free state, such as gold and diamonds, but most of the elements found in a bound state as a compound. Elements can be grouped into metals, non-metals, and metalloids / metal.

2. The element emblem

To simplify the name of the element, the scientists provide the element symbol. Coat of elements used until now made by Jons Jacob Berzelius. Here is a way of writing the symbol of the elements proposed by Jons Jacob Berzallius.

Is a chemical element that can not be subdivided into smaller substance, or can not be converted into other chemical substances using ordinary chemical methods. The smallest particle of an element is an atom. An atom consists of a nucleus of an atom (nucleus) surrounded by electrons. Atom consists of a nucleus of protons and neutrons. Until now there are approximately 117 known elements in the world.

The chemical compound is a single substance which is formed of several elements by chemical reaction and these compounds can also be broken down into its constituent elements by the chemical reaction. For example, dihydrogen monoxide (water, H2O) is a compound composed of two hydrogen atoms for every oxygen atom.

In general, this fixed ratio must be fixed due to the nature of physics, not a selected ratio of men. Therefore, materials such as brass, the superconductor YBCO, the semiconductor &aluminum gallium arsenide&, or chocolate are considered mixtures or alloys rather than compounds.

The characteristics that distinguish compound is that it has a chemical formula. The chemical formula gives the ratio of atoms in a substance, and the number of atoms in a single molecule (thus the formula for ethene is C2H4 and not CH2. The formula does not mention whether the compound is composed of molecules; for example, sodium chloride (common salt, NaCl is an ionic compound ,

The compound can form in several phases. Most of the compounds can be in the form of solids. Molecular compound may also be a liquid or a gas. All compounds will decompose to smaller compounds or individual atoms if heated to a certain temperature (called the decomposition temperature).

A. Halogen

a. Halogen Chemical Properties

1) Halogen is highly reactive groups in accepting electrons and acts as a strong oxidizing agent in one group. Growing up, the stronger the oxidizing agent.

2) halogen Electronegativities the Group increasingly greater upward. The most electronegative element than any other element in the periodic system is fluorine (note the data electronegativity).

3) The radius of the halogen atom in the group getting to the top of the smaller (note data). This means getting to the top of the smaller molecular size, then the attractive force between molecules (Van der Waals forces) will become smaller. Note also the boiling point and melting point, the more up vanishingly small.

Noble gas elements in the periodic system occupies a Group VIII A of the element Helium (He), Neon (Ne), Argon (Ar), krypton (Kr), Xenon (Xe) and radon (Rn). The structure of the outer electron octet noble gas (8) (except helium duplet (2)) is the most stable structure, therefore it is difficult noble gases react with other elements, so-called inert gas (slow). In 1962 Neil Bartlett succeeded in synthesizing a noble gas compound that is XePtF6. In the short time that other chemists showed that xenon can react directly with Fluor forming XeF2, XeF4, and XeF6. Since then the term inert is no longer appropriate and chemists began referring to the group of noble gases.

Alkaline earth metal element (IIA) is composed of Be, Mg, Ca, Sr, Ba, and Ra. This class has properties similar to the class IA. The difference is that it has a group IIA ns2 electron configuration and is a strong reducing agent. Although tougher than class IA, class IIA but is still relatively soft, shiny silver, and has a melting point and a higher density.

The elements in the third period consists of metal elements (Na, Mg, Al), metalloids (Si), non-metallic (P, S, Cl), and a rare gas (Ar). Electronegativities elements of the third period the greater the further right due to their atomic radius which is getting to the right is getting smaller. Antaratom in metal bonding strength increases (from Na to Al). This relates to the gain valence electrons. Silicon is a semiconductor / insulator because

including metalloid. This element has a very large covalent bonds, as well as phosphorus, sulfur, and chlorine which is an insulator because it includes non-metals (Source: http: //www.chem-is-try.org).

1. Nature of Transition Metals

All the elements of the transition is a metal, which is a soft, shiny, and electrically and heat. Silver is a transition element that has the highest electrical conductivity at room temperature and copper in second place. Compared with class IA and IIA, transition metal elements harder, has a melting point, boiling point, and higher density. This is because the transition elements share electrons in the skin d and s, so the bond is getting stronger.

2. Oxidation Numbers

Unlike class IA and IIA only has the oxidation number of +1 and +2, transition metal elements have several oxidation numbers. As vanadium has the oxidation number of +2, +3, and +4.

3. Nature of Magnetism

Every atom and molecule has magnetic properties, that is paramagnetic, in which atoms, molecules, or ions bit can be pulled by magnetic fields because there is an unpaired electron in the orbital and diamagnetic, in which atoms, molecules, or ions can be rejected by a magnetic field because all electrons in orbit in pairs. While in general the transition elements are paramagnetic because they have unpaired electrons in the d orbitals her. Paramagnetic properties of this would be stronger if the number of unpaired electrons in the orbital more. Metals Sc, Ti, V, Cr, and Mn is paramagnetic, while Cu and Zn is diamagnetic. For Fe, Co, and Ni are ferromagnetic, ie the same conditions as paramagnetic only in the solid state.

4. Ion Color

The energy levels of electrons in the transition elements are almost the same cause of color in transition metal ions. This happens because electrons can move to a higher level by absorbing visible light. In the transition class, the 3d subshell is not fully charged causes the electrons in the subshell it absorbs light energy, so that electrons are excited and emit light energy with a color that matches the color of light that can be reflected upon returning to the ground state. For example, purple Ti2 +, Ti4 + colorless, pink Co2 +, Co3 + blue, and so forth.