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From wiki:Lead(II) nitrate does not occur naturally. The compound can be obtained by dissolving metallic lead in aqueous nitric acid:[7][11]
3 Pb (s) + 8 H+ (aq) + 2 NO−3 (aq) → 3 Pb2+ (aq) + 2 NO (g) + 4 H2O (l)
More commonly, lead(II) nitrate is obtained by dissolving lead(II) oxide, which is readily available as a mineral, in aqueous nitric acid:[7]
PbO (s) + 2 H+ (aq) → Pb2+ (aq) + H2O (l)
In either case, since the solvent is concentrated nitric acid (in which lead(II) nitrate has very low solubility) and the resulting solution contains nitrate ions, anhydrous crystals of lead(II) nitrate spontaneously form:[11]
Pb2+ + 2 O−3 → Pb(NO3)2 (s)
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