Lead(II) nitrate preparation
Preparation: Into 100ml flask place 20g lead pieces or metal sheets and pour 40,6ml 40% nitric acid. (Acid can be prepared from 22,5ml concetrated (65%) nitric acid and 19,5ml water.) Heat the mix under reflux till most of lead will dissolve, if some white crystals will precipitate, add small amount of water. You can see in the reflux some brown gases - it's nitrogen(IV) oxide yielding from reaction between oxygen in air and nitrogen(II) oxide evolved by mix in flask. Because of this is much better to work under fume cupboard. Filter prepared solution, thicken it and cool with water and crushed ice. Filter out white crystals of product, wash with 10ml of alcohol and dry at 100oC.
Theoretical yield is 32,16g, practical is about 80% (26g).
3Pb + 8HNO3 ==> 3Pb(NO3)2 + 2NO + 4H2O
Properties: White crystalline solid, easy soluble in water. Usable for preparation of many other lead compounds, for example lead(IV) oxide, lead(II) sulfate or lead(II) chloride. By heating is decomposed into PbO.
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