Ionization

report about ionization

1. ionization SUB:analytical chemistry University of zakho facualty of science chemistry Department Prepared by : Pairaw Abdulkhalq Aziz Class:A Group:A Supervisor: Dr.Nidhal

2. List of content Introduction Ionization in liquid Ionization in gas Ionization energy The reference

3. introduction Ionization or ionisation , is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons to form ions, often in conjunction with other chemical changes . Ionization can result from the loss of an electron after collisions with subatomic particles, collisions with other atoms, molecules and ions, or through the interaction with electromagnetic radiation. Heterolytic bond cleavage and heterolytic substitution reactions can result in the formation of ion pairs. Ionization can occur through radioactive decay by the internal conversion process, in which an excited nucleus transfers its energy to one of the inner-shell electrons causing it to be ejected.

4. Ionization in liquid ionization often occurs in a liquid solution. For example, neutral molecules of hydrogen chloride gas, HCl , react with similarly polar water molecules, H2O, to produce positive hydronium ions, H3O+, and negative chloride ions, Cl-; at the surface of a piece of metallic zinc in contact with an acidic solution, zinc atoms, Zn, lose electrons to hydrogen ions and become colourless zinc ions, Zn2+

5. Ionization in gas Ionization by collision occurs in gases at low pressures when an electric current is passed through them. If the electrons constituting the current have sufficient energy (the ionization energy is different for each substance), they force other electrons out of the neutral gas molecules, producing ion pairs that individually consist of the resultant positive ion and detached negative electron. Negative ions are also formed as some of the electrons attach themselves to neutral gas molecules. Gases may also be ionized by intermolecular collisions at high temperatures.

6. Ionization energy The ionization energy increases going from the left to the right of the periodic table because elements toward the right of the table have smaller radii; the higher number of protons in the nucleus exert a greater force on the orbiting electrons, pulling them closer to the nucleus. Ionization energies increase from the bottom of the periodic table to the top because smaller atoms hold onto their electrons more tightly than bigger atoms. The reasoning behind this concept is that in bigger atoms, electrons orbit farther away from the nucleus; therefore, the protons in the nucleus exert less of an attractive force on the electrons. According to these general rules, helium is the element with the highest ionization energy.

7. The References https:// en.wikipedia.org/wiki/Ionization https:// www.britannica.com/science/ionization