Chapter 18, Problem 80QAP

Carbon-14 (C-14) with a half-life of 5730 years decays to nitrogen-14 (N-14). A sample of carbon dioxide containing carbon in the form of C-14 only is sealed in a vessel at 1.00-atmosphere pressure. Over time, the CO₂ becomes NO₂ through the radioactive decay process. The following equilibrium is established:
   $2{\text{NO}}_2\left(g\right)\rightleftharpoons {\text{N}}_2{\text{O}}_4\left(g\right)$
If the equilibrium constant for the equation as written is $1\times {10}^{-5}$ , what is the pressure of N₂O₄ after 20,000 years? Assume that the CO₂ does not participate in any chemical reactions.