38 
DR. A. E. H. TUTTON ON THE 
Volume. 
Relative Density. —Four determinations by the immersion method yielded the 
following values :— 
I. 
Density for 13°'8/4° 
. 1'9267 
For 20°/4° . 
. . F9255 
II. 
„ 13°-3/4° . . 
. 1 ‘9268 
„ 20°/4° . 
. . F9255 
III. 
„ 13°-6/4° . . 
. D9273 
„ 20°/4° . 
. . 1-9261 
IV. 
13°-6/4° . . 
. 1-9270 
„ 20°/4° . 
. . F9258 
Mean . 
. . 1-9257 
Accepted value for 20°/4°, 1'926. 
This appears 
to be the first determination of the 
specific gravity of ammonium copper sulphate. 
Molecular Volume .— ^ = 206'08. 
a 1'926 
Molecular Distance Ratios (topic axial ratios ).— 
x : -R : co = 61786 : 8‘2790 : 41942. 
Redeterminations of Densities of Alkali-metal Copper Sidphates. 
Potassium Copper Sidphate, KXu (S0 4 ) 2 .6H 2 0. 
Tlie crystals for this determination were freshly prepared for the purpose, as this 
salt is the most difficult of all the potassium salts of the series to obtain in crystals 
free from turbidity and efflorescence. The crystals employed were almost perfectly 
clear, and were used immediately after removal from the mother liquor. 
I. 
Density for 
14°-5/4° . . 
. 2-2336 
For 20°/4° . . 
. 2-2324 
II. 
5) 
15°-5/4° . . 
. 2-2335 
„ 20°/4° . . 
. 2-2325 
III. 
3 3 
15°-8/4° . . 
. 2-2329 
„ 2074 ” . . 
. 2-2320 
IV. 
33 
15°-9/4° . . 
. 2-2351 
,, 20°/4° . . 
. 2-2342 
Mean . 
. 2-2328 
Accepted value for 
20°/4°, 2-233. 
Rubidium Copper 
Sulphate , Itb 2 Cu (S0 4 ) 2 .6H 2 Q. 
I. 
Density for 
16°7/4° . . 
. 2-5761 
For 2074 o . . 
. 2-5753 
IT. 
3? 
16° '8/4° . . 
. 2-5752 
„ 2074 o . . 
. 2-5744 
III. 
3 3 
16°T/4° . . 
. 2-5751 
„ 2074 ° . . 
. 2-5741 
IV. 
33 
16°-2/4° . . 
. 2*5726 
„ 2074 o . . 
. 2-5716 
Mean . 
. 2-5739 
Accepted value for 20 /4°, 2'574 
