Non-metals The non-metals are the elements that have more than four electrons in their outermost energy levels, The non-metals are characterized by the smallest atomic sizes and the largest electronegativity.
The metals Metals are the elements that have less than four electrons in their outermost energy levels, During the chemical reactions, the atoms of the metallic elements tend to lose their outermost electrons, and...
The Red List The Red List is a list issued by the international union for conservation of nature (IUCN) every year, and indicates the endangered species, and the endanger level of each case, The...
If you go to the zoo, you will see a lot of different animals with different characteristics, and there is a variety among these animals in the shape and the way of feeding.
