Question

question 1 - 8
pure substances can consist of both elements and compounds.
what describes the relationship between elements and compounds?
carbon is always a part of a compound.
elements combine to form a compound.
compounds combine to form an element.
carbon changes to oxygen to form a compound.

Explanation:

• Option 1: Carbon can exist as an element (e.g., diamond, graphite), so it is not always part of a compound.
• Option 2: By definition, elements combine chemically in fixed ratios to form compounds. For example, hydrogen (\(H\)) and oxygen (\(O\)) combine to form water (\(H_2O\)).
• Option 3: Compounds are made up of elements. Elements are the simpler substances, and compounds are more complex. Compounds do not combine to form elements.
• Option 4: Carbon and oxygen are different elements. A compound is formed when elements combine, not when one element changes into another.

Answer:

Elements combine to form a compound.