Chapter 5, Problem 19STP

To determine

To Explain: The change in the water’s temperature and thermal energy.

Explanation of Solution

Introduction:

When molecules and atoms of heated substance collide with each other, thermal energy or heat energy arises due to the rise in temperature of these substances.

Temperature is the measure of the average kinetic energy of the individual particles of a substance, therefore on adding 250 mL of water in a glass containing 250 mL of water at ${30}^{\text{o}}\text{C}$ , the average kineticenergy of the individual particles become half and as a result the temperature of the water glass also decreased to half approximately. i.e. ${15}^{\text{o}}\text{C}$ . The thermal energy throughout the whole process would be same.

Conclusion:

Hence, the water’s temperature changes to ${15}^{\text{o}}\text{C}$ while the thermal energy remains same.