Prescription painkillers, also known as opioid pain relievers, include oxycodone, hydrocodone, hydromorphone, and others. Many people who abuse these painkillers become dependent. Some even move on to abusing illegal narcotics, such as heroin.
The first 92 (through uranium) occur naturally. The others are transuranics.. As of 2009, there are 118 ending with ununoctium. All together there are 117 elements on the periodic table, 94 of which occur naturally on earth. According to Wikipedia, there are 117 elements that have been isolated or synthesized, with a gap between element 116 and element 118.
At the present time, the periodic table of elements has a total of 118 elements which have been discovered to date. The Madelung energy ordering rule describes the order in which orbitals are arranged by increasing energy according to the Madelung rule.