Chemistry Test

Describe the formation of a covalent bond by the sharing of a pair of electrons between two atoms

·         understand covalent bonding as a strong attraction between the bonding pair of electrons and the nuclei of the atoms involved in the bond

·         explain, using dot and cross diagrams, the formation of covalent compounds by electron sharing for the following substances: i hydrogen ii chlorine iii hydrogen chloride iv water v methane vi ammonia vii oxygen viii nitrogen ix carbon dioxide x ethane xi ethene.

hydrogen

chlorine

same as hydrogen but six more on outer shells

hydroge chloriede

water

methane

ammonia

carbon dioxide

ethane

ethene

·         recall that substances with simple molecular structures are gases or liquids, or solids with low melting points

·         explain why substances with simple molecular structures have low melting points in terms of the relatively…