Question

A student carefully drops a 9.0 g solid Zn pellet initially at 50.0°C into an insulated cup containing 30.0 g of water at 27.8°C. The student predicts that the temperature of the water will increase after the pellet is added. Which of the following statements is the best justification for the student's prediction? (A) The metallic bonds between Zn atoms will break when the Zn is exposed to the water molecules, releasing energy that will be absorbed by the water molecules. (B) Collisions between the water molecules and the surface of the Zn pellet will result in the transfer of energy, increasing the average kinetic energy of the water molecules. (C) The strength of the hydrogen bonds between the water molecules will increase when the Zn pellet is added, decreasing the average kinetic energy of the water molecules. (D)Collisions between Zn atoms in the solid will increase in frequency when the Zn is exposed to the water molecules, resulting in the transfer of energy to the surroundings.

Answer 1

Answer:

(B) Collisions between the water molecules and the surface of the Zn pellet will result in the transfer of energy, increasing the average kinetic energy of the water molecules.

Explanation:

The question above shows a case of energy transfer and movement of molecules in the generation of heat. Which can be explained as follows:

As you can see, in the question, the solid Zn pellet has a higher temperature than water. There is a physical concept that states that when two bodies of different temperatures come into contact, there is a transfer of energy between them that seeks to equal the temperature of the two bodies. For this reason, when the Zn pellet comes into contact with water, collisions will occur between the water molecules and the surface of the Zn sediment that will result in energy transfer.

However, instead of causing the temperature balance between the water and the Zn tablet, this allows the water to get a higher temperature, because the energy transmitted by zinc increases the kinetic energy of the water molecules. In this case, these tomboys start to move very fast, generating heat.

Answer 2

Answer: choice B

Explanation: Heat flows from high to low. After you convert the Celsius into kelvin the Zn pellet has 323K and the water has 301K which results the transfer of the heat energy of the pallet to the water. ( you don’t have to convert, but it just make it easier) hope this helped you :)