Diatomic molecules are molecules composed only of two atom s, of either the same or different chemical element s. The prefix di-means two in Greek. Common diatomic molecules are hydrogen (H 2), nitrogen (N 2), oxygen (O 2), and carbon monoxide (CO).he bond in a homonuclear diatomic molecule is non-polar and covalent. In most diatomic molecules, the elements are nonidentical. Prominent examples include carbon monoxide, nitric oxide, and hydrogen chloride, but other important examples include MgO and NaCl.
Africa, which developed the world's oldest human civilization, gave humanity the use of fire a million and half to two million years ago. It is the home of the first tools, astronomy, jewelry, fishing, mathematics, crops, art, use of pigments, cutting and other pointed instruments and animal domestication.In short Africa gave the world human civilization.illions of years ago human life started in Africa, Australopithecus aphaeresis and Australopithecus africanus and Australopithecus robustus were all key rungs in the development of humanity.
Overview and Timeline. The civilization of Ancient Egypt was one of the earliest in world history. It is usually held to have begun around 3000 BC, when the lower Nile Valley became unified under a single ruler.his period of history, between the civilization's beginnings in c. 3000 BC to its conquest by the Romans in 31 BC, was almost a thousand years longer than the period between 31 BC and the present day.