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Question
Define a compound. Give two points of evidence to show that sodium chloride is a compound.
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Solution
A compound is a substance made up of two or more elements combined together chemically in a fixed proportion by mass.
Sodium chloride (NaCl) is a compound because:
- It is made up of two elements, sodium and chlorine, and the nature of NaCl is completely different from its constituent elements.
- Sodium and chlorine are present in a fixed proportion in sodium chloride.
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