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Sodium chloride forms cubic crystals when crystallized from water, but octahedral crystals when crystallized from a urea solution. How does this observation relate to the law of constancy of interfacial angles?

1. The law remains applicable
2. The law does not hold universally
3. This is a case where the law is violated
4. None of these statements are accurate

Correct answer: The law remains applicable

Solution

The law of constancy of interfacial angles remains applicable because the internal crystal structure and the angles between corresponding faces of the crystals do not change, regardless of the external shape of the crystals formed from different solutions.

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