156 
IOWA ACADEMY OF SCIENCES. 
formed was titrated and the hydrogen was reduced to 
normal conditions and the amounts of zinc corresponding 
to each were calculated. The calculation of the reducing 
zinc was based upon the assumption that one molecule of 
the acid oxidized three atoms of zinc, or that when the 
acid is decomposed at all it is completely reduced to hydro- 
chloric acid, and the whole series of experiments support 
this view. The volumes of hydrogen given below are in 
all cases reduced to normal conditions. 
ZINC 
DISSOLVED. H. COLLECTED. HCl . FOUND. ZD. TO H. ZD. TO HCl 
1 0.7047 69.93 0.0925 0.2048 0.4979 
2 6627 63.11 .0892 .1857 ,.4803 
In the following an excess of 2 N. acid was used and all 
the zinc weighed was dissolved, and it was of the same 
sample as used in (1) and (2). As may be observed in (3) 
and (4) the amounts of hydrogen collected were very small 
and the oxidizing action of the acid was very much more 
pronounced. It was observed in both experiments that 
the evolution of hydrogen seemed to be very much more 
rapid near the beginning of the experiment. Though there 
was scarcely a visible residue it seems possible that as the 
zinc dissolves, impurities collect at the surface and in- 
fluence the character of the reaction. This influence would 
have been far less in (1) and (2) where the zinc taken was 
about three times the amount dissolved. It is the purpose 
to investigate this reaction farther, using several samples 
of redistilled zinc. 
ZINC 
DISSOLVED. H. COLLECTED. HCl . FOUND. ZD. TO H. Zn. TO HCl. 
(3) .3484 • 4.4 c.c. .0619 .0129 .3332 
(4) .4966 5.7 c.c. .0873 .0168 .4699 
Action of Chloric Acid on Aluminium. 
Except the statement of Tommasi * that a solution of 
chloric acid treated with aluminium showed after six 
hours only a trace of hydrochloric acid, there seems to be 
nothing in the literature concerning the action of the acid 
on this metal. Aluminium slowly dissolves in cold dilute 
* 1. c. 
