The main building block of a silicate mineral is silicon-oxygen tetrahedron.Silicon-oxygen tetrahedron belongs to the anionic group and the silicon atom is surrounded by four oxygen atom, arranged to determine the edges of a tetrahedron.
This silicate ion consists of one silicon atom, placed in the middle of a tetrahedron and surrounded by four oxygen atom, placed at vertices of a tetrahedron.
positive deviation from raoults law means when the vapour pressure is higher than the solution is expected to exhibit e.g of one is the mixture of acetone and ethanol
negative deviation means that it is opposed to the total vapour pressure of the solution
