Silicon forms giant covalent molecules in which each Si atom is covalently bonded to 4 other. Si atoms. Covalent bonds are strong (comparable to metallic bonds) and as each Si atom. forms 4 of them all 4 bonds must be broken to separate the atoms and Si has a very high b.p.,
Chiffon, which is a French word for rag, is a lightweight sheer material with a slightly rough feel to it.It can be made from cotton, silk or synthetic fibers, but is usually associated with silk or nylon. Chiffon can be dyed to almost any shade desired, however if made from polyester it is difficult to dye.t tears very easily inside a washing machine, and a garment made of chiffon can rip apart while the wearer is sleeping in it. Most chiffon nowadays is made from polyester (for stain resistance) which is woven as a stretch-knit fabric. Stretch-knit is a way of making non-stretchable fabrics stretch.
/ÊÉªËfÉn/ , shiff-ON, from the French word for a cloth or rag) is a lightweight, balanced plain-woven sheer fabric woven of alternate S-and Z-twist crepe (high-twist) yarns. The twist in the crepe yarns puckers the fabric slightly in both directions after weaving, giving it some stretch and a slightly rough feel.hiffon is made from cotton, silk, or synthetic fibers. Under a magnifying glass it resembles a fine net or mesh which gives chiffon some see-through properties.