Atoms of the same element with different mass numbers are called isotopes
Answer : Option D) The particles move enough that they are not fixed in place, and the liquid can flow.
Explanation : The kinetic energy of the particles are allowed to move freely and are in motion when in the liquid state whereas the intermolecular particles can just flow; as the intermolecular attractions between the particles allows the liquid to flow by giving them a force to flow.
The answer is A) Aluminum Bromide
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