Help
Add this page to your book
Show book (0 pages)
Suggest pagesElectrovalency
 |
This article does not cite any references or sources. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (December 2009) |
 |
This article is an orphan, as few or no other articles link to it. Please introduce links to this page from related articles; suggestions may be available. (December 2009) |
'Electrovalency is the type of chemical bonding, that is established by the actual transference of one or more valence electrons, from a metallic atom to a non-metallic atom, so that each of the 2 elements can attain the stable electronic configuration of their respective nearest inert elements in the periodic table. This results in the formation of oppositely charged ions(cation and anion) which are held by electrostatic force of attraction and they in turn form an electrovalent compound.'For example, Na and Cl will form an electrovalent compound NaCl. So first Na(11), being a metal, will give away 1 electron to attain the stable state of Neon(10), its nearest inert element. Then Na will become (Na+). That 1 electron will be accepted by Cl(17) so that Cl can attain the stable state of Argon(18), its nearest inert element. Cl will thus become (Cl-). So Na+ + Cl- = NaCl
Electrovalency is a measurement of the net electric charge of an ion and is used when balancing chemical reactions. Electrovalency is related to the concepts of electronegativity and valence electrons, and indicates the number of electrons necessary for an ion to have a balanced electric charge.
Atoms that have an almost full or almost empty valence shells tend to be very reactive. Atoms that are strongly electronegative (as is the case with halogens) often only have one or two missing electrons in their valence shell, and frequently bond with other molecules or gain electrons to form anions. Atoms that are weakly electronegative (such as alkali metals) have relatively few valence electrons that can easily be lost to atoms that are strongly electronegative. As a result, weakly electronegative atoms tend to lose their electrons and form cations.
The electrovalency of an element or compound is expressed as a charge. Atoms or molecules that have lost electrons have an electrovalency greater than zero and are known as cations. When an atom or molecule gains electrons, it is called an anion. When an atom or molecule has an electrovalency of zero, it has no net electric charge. When writing about an ion, the convention is to write the chemical formula followed by the electrovalency as a superscript, illustrated below:
Ag+, Co2+, Fe3+, CN−, CO32−, PO43−. When an ion only contains a single atom it is called a monatomic ion, and when it contains more than one atom, it is called a polyatomic ion. On the above list, Ag+ would be a monatomic cation and PO43− would be a polyatomic anion.
Contents |
[edit] Electrovalency tables
These tables show the charges of ions formed by common elements and compounds. These tables are used to determine the proportion of a particular element in a compound, and also to predict the products of a reaction.
For information on naming conventions, see the chemical nomenclature pages for organic and inorganic compounds
[edit] Table of common anions
| −1 | −2 | −3 |
| Dihydrogen phosphate (H2PO4−) | Monohydrogen phosphate (HPO42−) | Phosphate (PO43−) |
| Hydrogen carbonate (HCO3−) | Carbonate (CO32−) | Nitride (N3−) |
| Hydrogen sulfate (HSO4−) | Sulfate (SO42−) | |
| Hydrogen sulfite (HSO3−) | Sulfite (SO32−) | |
| Hydrogen sulfide (HS−) | Sulfide (S2-) | |
| Aluminate (Al(OH)4−) | Zincate (Zn(OH)42−) | |
| Superoxide (O2−) | Oxide (O2−) | |
| Hydride (H−) | Peroxide (O22−) | |
| Fluoride (F−) | Thiosulfhate (S2O32−) | |
| Chloride (Cl−) | Chromate (CrO42−) | |
| Bromide (Br−) | Dichromate (Cr2O72−) | |
| Iodide (I−) | Silicate (SiO32−) | |
| Hydroxide (OH−) | ||
| Acetate (ethanoate) (CH3COO−) | ||
| Hypochlorite (ClO−) | ||
| Chlorate (ClO3−) | ||
| Nitrate (NO3−) | ||
| Nitrite (NO2−) | ||
| Cyanide (CN−) | ||
| Permanganate (MnO4−) |
[edit] Table of common cations
| +1 | +2 | +3 | +4 |
| Copper I (Cu+) | Copper II (Cu2+) | Aluminium (Al3+) | Tin IV (Sn4+) |
| Silver (Ag+) | Iron II (Fe2+) | Iron III (Fe3+) | Lead IV (Pb4+) |
| Hydrogen (H+) | Beryllium (Be2+) | Chromium III (Cr3+) | |
| Lithium (Li+) | Magnesium (Mg2+) | ||
| Sodium (Na+) | Calcium (Ca2+) | ||
| Potassium (K+) | Strontium (Sr2+) | ||
| Ammonium (NH4+) | Barium (Ba2+) | ||
| Hydronium (H3O+) | Manganese II (Mn2+) | ||
| Zinc (Zn2+) | |||
| Mercury I (Hg22+) | |||
| Mercury II (Hg2+) | |||
| Tin II (Sn2+) | |||
| Lead II (Pb2+) |
[edit] Electrovalency in chemical reactions
Electrovalency is used to help balance equations describing chemical reactions. In the following equation, hydronium and hydroxide combine to form water:
H3O+ + OH− → 2H2O0 One can see that the one positively charged hydronium molecule and one negatively charged hydroxide molecule have formed water which has an electrovalency of zero.
