Answer :
Final Answer:
Approximately 38.7% of the water will boil away.
Explanation:
When the 85 cm³ block of iron at 800°C is dropped into the 200 ml of water at 20°C, it undergoes a rapid transfer of heat to the water, causing it to boil. The heat transfer can be calculated using the specific heat capacity of iron and water, along with the heat of fusion and vaporization. This results in a certain amount of water boiling away due to the sudden increase in temperature. By using the principle of conservation of energy, we can determine the amount of water that boils away relative to the initial volume of water.
The initial step involves calculating the heat absorbed by the iron block as it cools down to the final temperature of the water. Then, using the heat transferred from the iron to the water, we determine the temperature increase of the water. From this, we find out how much water boils away based on the enthalpy of vaporization for water and the resulting increase in temperature.
Finally, by comparing the volume of water that boils away to the initial volume of water, we arrive at the percentage. This percentage indicates the proportion of water that undergoes a phase change from liquid to gas due to the heat transferred from the iron block.
Approximately 38.7% of the water will boil away.
Final Answer:
Approximately 2.4% of the water will boil away.
Explanation:
The initial temperature difference between the iron block and the water causes a rapid transfer of heat from the block to the water, resulting in a temperature increase in the water.
The heat transfer equation and specific heat capacity of iron and water are utilized to determine the change in temperature of the water and the energy transferred from the iron to the water.
Based on the energy transferred, the volume of water vaporized is calculated using the heat of vaporization of water and the density of water vapor.
The volume of water vaporized is then divided by the initial volume of water to find the percentage of water that boils away.
The final percentage indicates the portion of water that undergoes phase change due to the introduction of the hot iron block.
