(N/A) Boron,being an extremely hard refractory solid with a high melting point,low density,and very low electrical conductivity,finds many applications.
$1$. Boron fibers are used in making bullet-proof vests and light composite materials for aircraft.
$2$. The boron-$10$ $({}^{10}B)$ isotope has a high ability to absorb neutrons; therefore,metal borides are used in the nuclear industry as protective shields and control rods.
$3$. The main industrial application of borax and boric acid is in the manufacture of heat-resistant glasses (e.g.,Pyrex),glass-wool,and fiberglass.
$4$. Borax is also used as a flux for soldering metals,for heat,scratch,and stain-resistant glazed coatings on earthenwares,and as a constituent of medicinal soaps.
$5$. An aqueous solution of orthoboric acid is generally used as a mild antiseptic.