The salt ammonium nitrate can follow three modes of decomposition: (a) to \(\mathrm{HNO}_{3}(g)\) and \(\mathrm{NH}_{3}(g)\), (b) to \(\mathrm{N}_{2} \mathrm{O}(g)\) and \(\mathrm{H}_{2} \mathrm{O}(g)\), and (c) to \(\mathrm{N}_{2}(g), \mathrm{O}_{2}(g), \text { and } \mathrm{H}_{2} \mathrm{O}(g)\). Calculate \(\Delta G_{\mathrm{rxn}}^{\circ}\) for each mode of decomposition at 298 K. Explain in light of these results how it is still possible to use ammonium nitrate as a fertilizer and the precautions that should be taken when it is used.
Text Transcription:
HNO_3(g)
NH_3(g)
N_2O(g)
H_2O(g)
N_2(g)
O_2(g)
H_2O(g)
Delta G_^circ rxn
CH 231-001 Week 3 Notes I. Chapter 1 Week 3 Notes a. Resonance i. Resonance Theory – the representation of a single molecule at a single point in time by two or more Lewis structures having the same placement of all atoms but showing (not having) a different. Arrangement of pi electrons 1. Contributing structures – individual Lewis structures 2. Resonance Hybrid – molecule, ion, or radical described as the composite of all contributing structures 3. Resonance Arrow a. Do NOT use equilibrium or reaction arrows!! ii. Curved Arrow Notation – arrow starting at the electron source and ending at the electron destination 1. Electron-pushing arrow a. Shows electron distribution or movement in resonance NOT movement of an atom or positive charge i. Do NOT move positive charges with a curved arrow iii. Notes about resonance 1. Show that pi electrons are delocalized over several atoms – important stabilizing effect 2. Resonance stabilized – molecule with two or more reasonable resonance structures 3. Individual resonance structures are imaginary – they are partial
