Is AlSi3O10 that's the silicate in biotite covalently bonded? if so how? As I understand only non mentals normally covalently bond together.
2007-03-20 20:20:54 · 2 answers · asked by Gideon 1 in Science & Mathematics ➔ Chemistry
Biotite is in the Sheet Silicate Class of minerals having tetrahedra bonded in sheets (Si4O10).
Other layers contain Al substituted for one of the Si. The electronegativity of Al is only 1.61 and Silicon is 1.9. For comparison Oxygen is 3.44.
The covalent nature of the bond is relative and is dependent upon the crystal structure of the mineral. The molecular orbitals allow for greater sharing of the electrons.
2007-03-22 06:22:14 · answer #1 · answered by Richard 7 · 8⤊ 0⤋
Some informations about Biotite - Normally it's the 'black' mineral in granites (mix of quartz, feldspate and mica = biotite).
Formulas
Chemical : K(Mg,Fe++)3[AlSi3O10(OH,F)2
Empirical : KMg2.5Fe2+0.5AlSi3O10(OH)1.75F0.25
I suggest you to see this link:
http://webmineral.com/data/Biotite.shtml
There you can see the a 'crystal' moving and the crystal structure, with the Physical and Optical properties of Biotite. The best part is watch the crystal moving. Maybe then you can understand the bonding.
2007-03-22 22:21:15 · answer #2 · answered by Apolo 6 · 0⤊ 0⤋