Examlex
The number of electrons in the valence shell of an atom is equal to the group number for the representative elements.
Hadean
The earliest eon in Earth's history, marked by extreme heat and uninhabitable conditions, spanning from about 4.6 to 4 billion years ago.
Prokaryotes
Microorganisms characterized by the absence of a nucleus, including bacteria and archaea.
Representatives
Individuals or entities that stand in for or act on behalf of others in a particular context or scenario.
Bacteria
Microscopic, single-celled organisms found in virtually all environments, both harmful and beneficial to humans.
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