Achemical bond formed when two atoms share two pairs of electrons is a bond; it is best described as a chemical bond formed when two atoms share two pairs of electrons is a bond; it is best described as double; ionic triple; covalent double; covalent single; covalent single; ionic

Double/  covalent double (the other setence is repeated!)

Explanation:

When an atom donates electrons and other gains electrons, they form ions and the bond is called the ionic bond. When the atoms share electrons between them, they form a molecule, and the bond is called the covalent bond.

The atoms can share one, two or three pairs of electrons in the same bond. If one pair is shared it's called a single bond or a covalent simple; if two pairs are shared it's called a double bond or a covalent double, and if three pairs are shared it's called a triple bond or a covalent triple.

on passing the small ampere of electric current through the tube made of ar and hg of cfl generates uv rays which excites the fluorescent and thus emits the high radiation by consumption of just 5- 12 w in comparison to incandescent light which requires more power such as around 40 - 55 w to lighten.

moreover the life span of fluorescent or cfl is around 8000 h whereas the life span of incandescent is around 1200 h

hence, the building installed with incandescent lights bears more electricity bill.