Which substance has particles vibrating the fastest?

Which substance has particles vibrating the fastest?

• A. Boiling water
• B. Frozen water
• C. Room-temperature water
• D. Cold tap water

Answer: (A)

When particles have more energy, they vibrate and move faster. Boiling water is at the highest temperature among the options, so its water molecules have the most kinetic energy on average. Frozen water has very little motion because it’s solid; room-temperature water has more energy than ice but less than boiling water; cold tap water is even cooler, so its molecules vibrate more slowly than those in boiling water. So the boiling water has particles vibrating the fastest.

When particles have more energy, they vibrate and move faster. Boiling water is at the highest temperature among the options, so its water molecules have the most kinetic energy on average. Frozen water has very little motion because it’s solid; room-temperature water has more energy than ice but less than boiling water; cold tap water is even cooler, so its molecules vibrate more slowly than those in boiling water. So the boiling water has particles vibrating the fastest.