To determine the enthalpy of water at a specific condition, we need to use the steam tables or a thermodynamic property calculator. Here's how you can do it using steam tables:
1. Use the given pressure of 850 kPa to locate the saturated water properties in the steam tables. Look for the table that provides information for saturated water (liquid) properties at various pressures.
2. Locate the closest pressure value to 850 kPa in the table. Since water exhibits a range of properties depending on the pressure, it's important to find the right value for accurate results.
3. Once you have located the correct pressure value, note down the enthalpy value corresponding to saturated water (liquid) at that pressure.
4. However, we need to consider that we are dealing with 5.0 kg of water, not just 1 kg as seen in the steam tables. Therefore, we need to multiply the enthalpy value obtained in step 3 by the mass of water (5.0 kg) to find the enthalpy of 5.0 kg of water at 850 kPa.
Keep in mind that the enthalpy value obtained represents the enthalpy of saturated water at that specific pressure. If the water is not saturated but in a superheated state, you would need additional information to determine the enthalpy accurately.
Alternatively, you can use a thermodynamic property calculator or software that provides accurate enthalpy values for water at specific conditions. These tools utilize advanced equations and algorithms to calculate properties without the need for referencing steam tables manually.