OPTIONS:3+3 [Hydration * Specific Gravity].  S.H. Shakman 

   A. Agreement (w/in 10%) between observed and calculated
conductivity values for majority of (49) positive ions calc. as per
1987 AAAS Abstract #111 (see [B]) may be extended to major-
ity of total 108 ions in CRC 1985, D167, when 3rd hydrational
assumption is allowed (max-per-Flint)/2. Ions in each of 3
below groups often relate sequentially &/or thru Mendeleev.:
  (1)Hydration # [H]=zero for all 12 listed positive
lanthanide ions; H+,OH-; Cs+,Rb+; SO3-2,SO4-2,S2O4-2;
  (2)H=maximum-per-Flint for Li+[H=19],Na+[11],K+[3]; Be++
[17],Mg++[9],Sr++[6]; HPO4-2[23],H2PO4-[21],H2PO2-[14];
  (3)(H=max-per-Flint)/2 for Mn++[H=19/2],Fe++[18/2],Co++
[17/2],Ni++[16/2],Cu++[15/2],Zn++[14/2]; F-[15/2],HF-[5/2],
Cl- [H=7/2],ClO2-[14/2],ClO3-[6/2],BrO3-[11/2],IO3-[16/2].

Abegg & Bodlander in 1899[Z.Anorg. Chem.20,491] thought
resp. conductivities evidenced anhydrous H+ & OH- ions;
Flint indicated such for H+,Rb+,Cs+ w/Cl- [1932,p.233].

Bousfield in 1906[Phil.Trans.206A,124] posited H=3.5 for Cl-.

Error       Pos (49)       Neg (59)       Total (108)
            max l/2  0   T   max 1/2  0  T   max 1/2  0  T
w/in 10%      8   6 18  32     8   8  9 25    16  14 27 57
w/in 20%      8   8 19  35    17  11 11 39    25  19 30 74

   B. Flint in 1964 [Behavior Patterns...,Chs.3,15] derived
hydrated volume (Vh) as a function of anhydrous (Wa) and hydra-
ted (Wh) wts. [Vh=Wh/(1+Wa/Wh)]; subtracted Vh in cc from 1000
to derive volume of free water in a 1-liter solution; added
added same free-water amount in grams to wt. of hydrated sol-
ute; and divided result by 1000 to calculate specific gravity.

Curiously Flint used 2 distinct methods to determine ratio
(Wa/Wh) in above equation for Vh:
(1) ratio for total molecule [used in [G] 1987 AAAS Abstract#113; &
(2) average of individual ionic ratios.
As a 3rd option, individual ionic hydrated volumes might be summed.

[W.G. Ganong, Rev. of Med. Physiology (1975), p. 12]: "The ions
in the body are hydrated, and although the atomic weight of
potassium (39) is greater than that of sodium (23) the hydrated
sodium ion, i.e., Na+ with its full complement of water, is
larger than the hydrated potassium ion."

Encyclopedia Britannica (198?): "... the ions Cl-, Br-, and I- have
almost identical mobilities although it might be expected that the
heavy and bulky I- ion would a much lowermobility than the lighter
and smaller Cl- ion.  Even more surprisinigly, the small and light
lithium (Li+) ion has only about half the mobility of the heavy
cesium (cs+) ion."



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