Final answer:
The change in energy as work during the synthesis of ammonia with a volume change from 8.4 L to 4.9 L at 43.5 atm, is calculated as 15.42611875 kJ.
Step-by-step explanation:
To calculate the change in energy as work that occurs during the contraction of volume in the synthesis of ammonia, we use the work formula work = -PΔV, where 'P' denotes the constant external pressure and 'ΔV' denotes the change in volume. First, we need to convert the pressure from the atmosphere (atm) to pascal (Pa) because the standard SI unit for volume is cubic meters (m³). However, since we want our answer in kilojoules (kJ), we can directly convert the volume from liters (L) to cubic meters (m³) and the pressure from atm to kilopascals (kPa) and then calculate the work.
The change in volume (ΔV) is the final volume minus the initial volume, which is 4.9L - 8.4L = -3.5L.
To convert from liters to cubic meters, we use the conversion: 1L = 0.001 m³.
Therefore, the change in volume in cubic meters is -3.5L * 0.001 m³/L = -0.0035 m³.
The pressure is given in atm and converting it to kPa uses the conversion: 1 atm = 101.325 kPa.
Thus, the pressure in kPa is 43.5 atm * 101.325 kPa/atm = 4407.4625 kPa.
Now we can calculate the work done:
work = -PΔV
= -4407.4625 kPa * (-0.0035 m³)
= 15.42611875 kPa·m³.
Since 1 kPa·m³ is equivalent to 1 kJ, the work done is 15.42611875 kJ.