any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter

an abundant nonmetallic tetravalent element occurring in three allotropic forms: amorphous carbon and graphite and diamond; occurs in all organic compounds

a brittle grey crystalline element that is a semiconducting metalloid (resembling silicon) used in transistors; occurs in germanite and argyrodite

a soft heavy toxic malleable metallic element; bluish white when freshly cut but tarnishes readily to dull grey

a tetravalent nonmetallic element; next to oxygen it is the most abundant element in the earth's crust; occurs in clay and feldspar and granite and quartz and sand; used as a semiconductor in transistors

a silvery malleable metallic element that resists corrosion; used in many alloys and to coat other metals to prevent corrosion; obtained chiefly from cassiterite where it occurs as tin oxide