Answer:
A chemical change is required to separate the elements present in it.
Explanation:
The only true statement from the choices given is that water as a pure substance requires a chemical change to separate the elements present in it.
Water is a molecule consist of two atoms of hydrogen and one atom of oxygen.
- The atoms are covalently bonded together.
- A chemical process, the electrolysis of water is often used to separate the atoms of a water.
- Physical changes cannot be used to separate the atoms of water.
- Water is a compound which consists of two elements.
Therefore, we see that only the first choice satisfies this problem.
