Engineering Board Exam Reviewer · Chemistry · medium

Air is 21% oxygen by mole. What is the partial pressure of oxygen when the total pressure is 760 mm Hg?

  1. 159.6 mm Hg
  2. 760.0 mm Hg
  3. 21.0 mm Hg
  4. 600.4 mm Hg

Answer

A. 159.6 mm Hg

Solution

P O2 = y P = 0.21(760) = 159.6 mm Hg.

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