Abstract
From the study of former data, a general relationship was found to exist between the vapour pressure depression and ionic concentration of saturated solutions of single inorganic salt.
A theory, similar to the Dalton's partial pressure law, was established on the v. p. d. of a sat. soln. consisting of inorganic salts, follwing experimental proof of a hypothesis derived from the above-mentioned information, using a newly devised humidity measuring apparatus. The theory is that.
ΔP=ΣΔP'n
where ΔP'n=C'n·ΔNn
and ΔNn=ΔPn/Cn
Contrary to the case of diluted soln., the solute in a sat. soln. has its own v. p. d. characteristics shown as the specific molecular depression, by which the influence of impurities on the humidity of inorganic salt crystals could be determined quantitatively. The v. p. d. characteristics of a salt in a sat. soln. can be explained from the view point of hydration.
n: foot note n indicates the kind of salt
ΔP: total v. p. d. of a sat. soln. consisting of two or more salts
ΔP'n: partial v. p. d. of a salt in a sat. soln, consisting of two ormore salts
ΔPn: v. p. d. of a sat. soln. of a single salt
Cn: concentration of a sat. soln, of a single salt
C'n: c. of a particular salt in a sat. soln. consisting of two or more salts
ΔNn: specific molecular depression of v. p. in a sat. soln.
