Final answer:
To convert 400 mm Hg to kPa, you use the conversion factor that 1 atm is equivalent to 760 mm Hg and 1 atm is 101.325 kPa. Multiplying these together, 400 mm Hg is equal to 53.0325 kPa.
Step-by-step explanation:
To express the pressure of 400 mm Hg in kPa, we must use a conversion factor.
The pressure unit conversion between millimeters of mercury (mm Hg) and kilopascals (kPa) is based on the equivalence of 760 mm Hg to 1 atmosphere (atm) and 1 atm being equivalent to 101.325 kPa.
Using this information, we can set up the conversion factor to convert from mm Hg to kPa:
400 mm Hg x (1 atm / 760 mm Hg) x (101.325 kPa / 1 atm)
= 53.0325 kPa
Therefore, 400 mm Hg is equal to 53.0325 kPa.