There are seven metalloids in the periodic table, including boron, silicon, germanium, arsenic, antimony, tellurium, and astatine. They are given the name metalloid mainly in light of their physical resemblance to metals. Chemically the metalloids generally behave like (weak) nonmetals. They have moderate ionisation energies, low to high electron affinities, moderate electronegativity values, are poor to moderately strong oxidising agents, and demonstrate a tendency to form alloys with metals.
Periodic Table 