Giant Covalent Structures - Silicon Oxide
Chemistry: Cambridge International GCSE Supplement, topic 2.6.4
Silicon Dioxide (Silica)
Silicon dioxide (silica) is a giant covalent structure. Silica's empirical formula is SiO2. Silica has the following properties:
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Covalent bonds
- Each silicon atom is covalently bonded to 4 oxygen atoms.
- The oxygen atoms bridge between two silicon atoms to build up a giant-covalent structure.
Hard
- Like diamond, there are lots of strong covalent bonds in silica. This makes it very hard.
Semi-conductor
- Silica is a semi-conductor. This makes it useful in electronics: most transistors are made of silica.
High melting point
- A lot of energy is needed to break strong covalent bonds.
- Silica has lots of strong covalent bonds. This means that it has a high melting point.
Test yourself on Giant Covalent Structures - Silicon Oxide
Which of these are properties of silica?
What is the empirical formula for silica?