Home › CSEE (Form 4) › Chemistry › Classification of Matter › What must always be true of the elements inside …
What must always be true of the elements inside any compound?
AThey can be mixed in any ratio
BThey keep all their own properties
CThey are joined in a fixed ratio
DThey can be split by filtering
Answer & Solution
Correct answer: C. They are joined in a fixed ratio
1. A compound is a substance made of two or more different elements joined together in a fixed ratio.
2. Water always has two hydrogen atoms for every one oxygen atom, no matter where the sample came from.
3. That fixed ratio is what the chemical formula records.
4. Being able to mix in any ratio and being separable by filtering both describe mixtures instead.
_Source: Siyavula Physical Sciences Grade 10 (Everything Science, CC BY 4.0), Chapter 2: Classification of matter_