Chemistry Spl

Naming of straight chain alkanes (alkanes that do not branch) is a straightforward process. To give an alkane a name, a prefix indicating the number of carbons in the molecule is added to the suffix ane, identifying both the kind of molecule (an alkane) and how many carbons the molecule has (the prefix). The name pentane, for example, tells you that the molecule is an alkane (thus the ane ending) and that it has five carbons (pent indicates five). Prefixes for alkanes that have 1-4 carbons are rooted historically. These are methane, ethane, propane, and butane, respectively. On the other hand, for 5 carbons and up a prefix derived from greek is given. (An easy way to remember the first four names is the anagram Mary eats peanut butter, standing for methane, ethane, propane, butane).

Look at where He is on the Periodic Table. It is one of the "Inert Gases". The reason all of these exist as gases in the monotonic form is because of the quantum mechanical nature of their electronic structure. Their electronic configuration or energy state is such that they are perfectly happy as they are. They do not need an extra electron or to share an electron or to give up an electron to be energetically "happy". Therefore, they do not chemically bond to any other atoms, not their own kind or any other kind. This "scientific law" has actually been violated (scientists found an exception). Researchers were able, by using very extreme conditions, to get Ar to react to form a coumpound that was "stable" under these very extreme conditions. As soon as the conditions changed, the Ar compound disintegrated and the Ar was left by itself again.