Final answer:
The partial pressure of nitrogen (PN₂) in a room with total air pressure of 0.987 atm is approximately 0.77 atm, calculated by multiplying the percentage of nitrogen in air (78%) by the total pressure.
Step-by-step explanation:
The partial pressure of nitrogen, PN₂, in a room where the total air pressure is 0.987 atm can be calculated using Dalton's Law of Partial Pressures which states the total pressure is the sum of all partial pressures of the gases present. Air is primarily composed of nitrogen and oxygen, with nitrogen typically comprising approximately 78% of the atmosphere. Hence, we can find PN₂ by multiplying the percentage of nitrogen in air by the total pressure.
PN2 = 0.78 × 0.987 atm = 0.76986 atm, which can be rounded to 0.77 atm (Option d).
This approximation assumes that the composition of air in the room is the standard atmospheric composition and that no other significant gases are contributing to the total pressure.