+ potassium chloride solution -^Lead chloride solution + potassium nitrate solution • Calcium Carbonate • Aluminium • Water 2.5 Mass spectrometer 29 3 The Mole 3.7.1 Example If 3g of Carbon is burned in oxygen. • The nuclear charge (+) pulls the outer edge of an atom e.g. Mg (g) -> Mg + (g) + 1.5 H 2 S0 4 -> C0 2 (g) + 10 H 2 0) have low melting and boiling points H He -259 -270 '253 -269 gas 2 gas Li Be B C N 0 F Ne 180 1280 2030 3500 -210 -219 -220 -249 1340 2500 3700 3900 -196 -183 -188 -246 solid solid solid gas gas K 63 Ca 850 4 3 5 symbol 760 1440 Key m.pt. (°C) solid solid solid solid solid solid.