The awareness of protecting natural life increased after great harmful consequences that appeared since the mid-twentieth century. As each species of the plant gets extinct, 30 species of animals that rely on it as...
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...
