Prices to Compare â effective June 1, 2017. Here are Penelecâs prices to compare by rate class. Your rate class is on the upper right. hand corner of your Usage Report. Use your figure to compare the prices offered by. different electric generation suppliers.
Sodium Chloride, NaCl. The classic case of ionic bonding, the sodium chloride molecule forms by the ionization of sodium and chlorine atoms and the attraction of the resulting ions. An atom of sodium has one 3s electron outside a closed shell, and it takes only 5.14 electron volts of energy to remove that electron. The chlorine lacks one electron to fill a shell, and releases 3.62 eV when it acquires that electron (it's electron affinity is 3.62 eV).
Na is a metal, and Cl is a nonmetal, so you have an ionic compound when they form. As for covalent bonds, they take place between two nonmetals ONLY. For example, you have carbon dioxide (later you will learn why you have to put di-in front of oxide).luminium oxide Al2O3 is ionic because of the presence of the metal ion, Al3+ and non-metal ion O2-. Methane CH4 is covalent as all the elements in it are non-metals. It has carbon and hydrogen, both of them are non-metals.