Note 20 — Chapter XIII · POTASSIUM, RUBIDIUM, CÆSIUM, AND LITHIUM. SPECTRUM ANALYSIS

As the atomic weight of potassium is greater than that of sodium, the volumes of the molecules, or the quotients of the molecular weight by the specific gravity, for potassium compounds are greater than those of sodium compounds, because both the denominator and numerator of the fraction increase. We cite for comparison the volumes of the corresponding compounds—

Na 24 NaHO 18 NaCl 28 NaNO₃ 37 Na₂SO₄ 54

K 45 KHO 27 KCl 39 KNO₃ 48 K₂SO₄ 66