{"id":7962,"date":"2018-06-03T16:05:11","date_gmt":"2018-06-03T16:05:11","guid":{"rendered":"https:\/\/www.experimentoscientificos.es\/?page_id=7962"},"modified":"2018-10-31T10:27:45","modified_gmt":"2018-10-31T10:27:45","slug":"enlace-ionico","status":"publish","type":"page","link":"https:\/\/www.experimentoscientificos.es\/en\/enlace-ionico\/","title":{"rendered":"Ionic Bonding"},"content":{"rendered":"

The ionic bond<\/strong> is the bond between a metal and a non-metal. In the following diagram of the\u00a0periodic table<\/a>\u00a0you can see the metallic elements (blue) and the non-metals or metalloids. The bonds that occur between metals and non-metals or metalloids are\u00a0ionic bonds<\/strong>.<\/p>\n

\"Enlaces<\/p>\n

The basis of a\u00a0ionic bond<\/strong>\u00a0is a bond where an atom with extra electrons to complete the last shell is joined with an atom that lacks electrons, so that both atoms are complete.<\/p>\n

An ionic bond can also occur between a negatively charged molecule and a metal (positively charged). This is the case with sulphates, which are formed by ionic sulphate bonds of different metals, hence their solubility.<\/p>\n

COMPOSITION OF ATOMS AND THEIR BONDS<\/h2>\n

Let's remember how the atom<\/a>\u00a0in order to understand the bonds it forms with other atoms. The atom is made up of protons<\/strong>, neutrons<\/strong> y electrons<\/strong>. Protons and neutrons are part of the nucleus and are not involved in bonding. It is the negatively charged electrons that are involved in chemical bonding.<\/p>\n

VALENCE ELECTRONS<\/span><\/h3>\n

The electrons in the orbitals of an atom are distributed in levels. In the first level, or first orbital, there can be up to 2 electrons, in the second 8, in the third 18, in the fourth 32. Depending on the number of electrons an atom has, levels are completed. In other words, the first two electrons go into the first level, the next two until the second level is covered, and so on.<\/p>\n

The number of electrons an atom has equals the number of protons, and this corresponds to the atomic number<\/a>. The atomic number is given by the position of the element in the periodic table<\/a>.<\/p>\n

CHARGES OF THE ATOM. OCTET RULE<\/span><\/span><\/h3>\n

An atom is stable the more complete each electron orbital is. As soon as it has too few or too many electrons to leave the last shell complete, it will tend to lose or gain them. If it has 7 electrons in the second shell, it will tend to gain one, so it gains 1 electron or, in other words, a negative charge. It will remain in a -1 oxidation state. This is the\u00a0oxidation number<\/strong>\u00a0 o\u00a0valencia<\/strong>\u00a0of an atom. You can see more detail at\u00a0oxidation numbers<\/a>.<\/p>\n

This is known as the octet rule or Lewis' law.<\/p>\n

Noble gases are the elements that do not react or share with anyone because they already have their last layer complete, hence their stability and low reactivity.<\/p>\n

The different combination or bonding of the electrons in the last shell<\/strong> between atoms can be made in several ways, the one we are going to look at here is ionic bonding, but covalent bonding or metallic bonding can also occur.<\/p>\n

IONS<\/h2>\n

Atoms that contain electrical charges are called ions (regardless of whether they are positive or negative). Negatively charged ions, produced by the gain of electrons, are known as anions (which are attracted to the anode) - Positively charged ions, resulting from a loss of electrons, are known as cations.<\/p>\n

ELECTRONEGATIVITY<\/h2>\n

The\u00a0electronegativity\u00a0<\/span>of an element measures its tendency to attract electrons to itself when it is chemically combined with another atom. The higher it is, the greater its ability to attract electrons.<\/p>\n

An atom with a very negative electron affinity and a high ionisation potential will attract electrons from other atoms and will also resist letting go of its electrons in the face of external attractions;\u00a0will be highly electronegative.<\/b><\/p>\n

Compounds consisting of elements with very different electronegativities<\/strong> tend to form bonds with a strong ionic character<\/p>\n

\"Electronegatividad\"<\/p>\n

EXAMPLES OF IONIC BONDING<\/h2>\n

CHEMICAL BONDING IN NACL. SODIUM CHLORIDE<\/h3>\n

Let's see what ionic bonding is like through sodium chloride, common salt, NaCl. The elements\u00a0sodium<\/a>\u00a0(Na) and chlorine (Cl) of which sodium chloride is composed.<\/p>\n

Na<\/strong>: The\u00a0sodium<\/a>\u00a0is element number 11 in the periodic table, which means that it completes the first shell (2 electrons), the second shell (8 electrons) and has 1 electron in the unstable third shell. It loses this electron, having\u00a0valence 1+<\/strong><\/p>\n

Cl:\u00a0<\/strong>Chlorine is the 17th element in the periodic table, missing 1 electron to complete the third shell. It tends to gain one electron, and therefore has a\u00a0valencia 1-<\/strong>.<\/p>\n

In the NaCl bond, sodium gives up an electron to chlorine, with sodium losing an electron and chlorine gaining an electron. This creates an ionic bond. Actually, it is not just 2 atoms that are joined together, but an ionic bond is created. ionic network<\/strong> like the one in the picture.<\/p>\n

\"enlace<\/p>\n

When dissolved in water, the ionic bonds are broken, creating Cl- and Na+ ions and conducting electricity through them. See\u00a0water conductivity<\/a>.<\/p>\n

CHEMICAL BONDING IN CUSO4. COPPER SULPHATE<\/h3>\n

Copper sulphate, with the formula CuSO4, is also a case of ionic bonding, where the sulphate anion molecule (SO42-), binds with the copper cation to form the sulphate through an ionic bond. Sulphates are known to be the most common form in which salts are found dissolved in water, so we have sulphates of magnesium, copper, potassium, calcium, and practically all the metals we know.<\/p>\n

Other common ionic bonds are: KCl (sodium chloride), KI (potassium iodide), CaCl2 (calcium chloride), FeO (iron (II) oxide), MnO2 (manganese), Li3N (lithium nitride), CaC2, as well as all sulphates.<\/p>\n

PROPERTIES IONIC BONDS<\/span><\/h2>\n

The elements with ionic bonds have common properties, which are detailed below:<\/p>\n