Sodium (2.8.1) has a valency of 1, thus it will lose 1 electron during chemical process, and it will become a positively charged ion. Sulfur (2.8.6) has a valency of 6, thus it will gain 2 electrons during chemical process, and it will become a negatively charge ion. Sodium is found in group I in the periodic table and Sulfur is found in group VI in the periodic table. Therefore sodium is metal and sulfur is non-metal. The physical properties of metal is that it conduct electricity well and non-metal is a poor conductor of electricity.

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