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Question
Give a reason for the following statement :
Zinc is considered an element, while zinc sulphide is considered a compound.
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Solution
Zinc [Zn] is an element as zinc is a pure substance made up of one kind of atoms all having the same size, atomic number and atomic mass.
Zinc sulphide [ZnS] is a pure substance made up of two-element [atoms] of zinc and sulphur combined chemically in a fixed proportion.
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