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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Ans 4) Chlorine-35 atom and Chlorine-37 atom are called isotopes... Use these two examples to explain what is 'isotopes'.

Defination of iostopes, different atoms of the same element which have the same number of protons but different number of electrons.

Chlorine-35 have a proton and neutron no. of 35.
Chlorine-37 have a proton and neutron no. of 37.
Both have the same number of 17 protons.
Chlorine-35 has 18 neutrons (35-17=18)
Chlorine-37 has 20 neutrons (37-17=20)

Therefore, Chlorine-35 and Chlorine-37 are isotopes.

{/Chemistry Ans 3) --

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Ans 3) Draw the atomic structure of a sulfur atom and a sulfide ion... Explain why you draw it in this way. Sulfur has a valency of 6. Sulfur needs to accept two electrons to achieve a full shell (2.8.8). When sulfur gains two electrons, sulfide ion is formed.