Answer:
4 valence electrons
Despite the fact that the word silicon has a ubiquitous affiliation with all things electronic, Si itself is not a good electrical conductor. It has 4 valence electrons, meaning that filling its outer shell it can form a very strong lattice with 4 neighboring Si atoms-with no un-bonded electrons remaining
Answer:
Air is a mixture. Its constituents can be separated. For example: oxygen, nitrogen etc.
Hydrochloric acid is a mixture, being an acidic liquid.
