Answer;
Independent; Mg2+ and Fe2+
-Independent SiO4 4– tetrahedra join with Mg2+ and Fe2+ ions to produce the mineral olivine in the rock peridotite.
Step-by-step explanation;
-The silicon-oxygen tetrahedron is a four-sided figure with a silicon atom in the middle bonded to four neighboring oxygen atoms.The simplest silicate structure, that of the mineral olivine, is composed of isolated tetrahedra bonded to iron and/or magnesium ions.
-Olivine is the name of a group of rock-forming minerals that are typically found in mafic and ultramafic igneous rocks such as basalt. Olivine is a magnesium iron silicate with the formula (Mg2+, Fe2+)2SiO4. Silica tetrahedra, made up of silicon and oxygen, form chains, sheets, and frameworks, and bond with other cations to form silicate minerals.