✔ 最佳答案
1. Diamond, graphite and silicon(IV) oxide they contain covalent bonds.
They are all in solid state because they have giant covalent structure which are held by strong covalent bonds. Hence boiling point and boiling point of them is very high.
2. I don't think that there is a compound with ionic bonds which exist as liquid or gaseous state in room temp. and pressure as ionic bonds are strong in nature. They usually have high boiling point and melting point.
3. The compounds with ionic bonds can conduct electricity in molten form only, while the compounds with covalent bonds cannot conduct electricity whether they are in solid or liquid state because the compounds with ionic bonds are electrolytes that contain mobile ions for conducting electricity.
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