Question

A scuba diver’s air tank contains oxygen, helium, and nitrogen at a total pressure of 205 atmospheres. The partial pressure of nitrogen is 143 atmospheres, and the partial pressure of helium is 41 atmospheres. What is the partial pressure of oxygen in the tank?

A. 21 atm
B. 103 atm
C. 307 atm
D. 389 atm

Answer 1

A. 21 atm
143+41=184
205-184=21 atm

Answer 2

Answer: A. 21 atm

Step-by-step explanation: According to Dalton's law of partial pressure, the total pressure of a gas mixture is the sum of partial pressures of individual gases.

Thus
`p_(total)=p_(O_2)+p_(He)+p_(N_2)`

Given:
`p_(total)`= 205 atm

`p_(He)` = 41 atm

`p_(N_2)` = 143 atm

Thus
`205atm=p_(O_2)+41atm+143atm`

`p_(O_2)=21atm`