Thermal energy is transferred to liquid water. As it heats up almost to boiling, which change can occur?
As liquid water heats up almost to boiling, several changes can occur:
1. Increase in temperature: The thermal energy being transferred to the water causes an increase in its temperature. As the temperature rises, the average kinetic energy of water molecules also increases.
2. Expansion: Heating up the water causes an increase in the average kinetic energy of its molecules. This increase in kinetic energy leads to an increase in the spacing between molecules, resulting in expansion of the water.
3. Formation of water vapor: If the water continues to heat up and reaches its boiling point, the thermal energy can cause some of the water molecules to overcome the intermolecular forces and escape from the liquid phase, forming water vapor. This process is called boiling or evaporation.
4. Change in density: As the water heats up, its density generally decreases due to the expansion mentioned earlier. However, when the water reaches its boiling point and begins to convert into vapor, the density of the remaining liquid may increase as water molecules are removed from the liquid phase.
5. Change in state: If the thermal energy transferred to the water is sufficient to reach the boiling point, a change in state occurs, and the liquid water transforms into a gas (water vapor). This change from the liquid phase to the gas phase is known as vaporization.