430 Dr. T. Andrews on the Heat disengaged duriyig iJie 



1. 2. 3. 



2611 2658 2547 



The primarj' compound formed in this reaction is probably 

 the chloride HgCl; but by the action of the excess of mer- 

 cury, a portion of it is aiierwards converted into the subchloride 

 Hg.jCl. We have, therefore, for the heat evolved during 

 the combination of — 



One litre chlorine with mercury . . 2605 

 One gramme chlorine with mercury . 822 

 One equivalent chlorine with mercury 3633 



Phosphorus and Chlorine. 

 1. 2. 



M 145-4 c.c. 144-6 c.c. 



B 29-85 in. 29-85 in. 



T ir'5 ll°-3 



E 0°-6 l°-3 



I l°-62 l°-62 



Ic 1=-61 1°-G3 



W 143-2 grms. 140-5 grms. 

 V 23-2 rrrms. 23*2 grms. 



1. 2. 



1924 1926 



The compound formed was the solid perchloride, P CI5, 

 accompanied by a small quantity of the terchloride, P CI3. 

 These experiments with phosphorus and chlorine can only be 

 considered to be imperfect approximations. 



We obtain, therefore, for the heat evolved during the com- 

 bination of — 



One litre chlorine with phosphorus . . 1925 

 One gramme chlorine with phosphorus . 607 

 One gramme phosphorus with chlorine . 3422? 

 One equivalent chlorine with phosphorus 2683 



Zinc and Chlorine. 



As dry chlorine gas has no action upon zinc at ordinary tem- 

 peratures, it was necessary to introduce a little watei' into the 

 vessel in which the reaction took place. In the experiment, 

 however, when thus arranged, two distinct sources of heat 

 existed ; one, the combination of the zinc and chlorine, the 

 other, the solution of the compound formed. To determine 

 the amount of the latter, an independent experiment was made; 

 and by subtracting it from the whole quantity of heat at first 

 obtained, there remained the increment of ten)perature due to 

 the chemical combination. A small quantity of subchloride 

 of zinc was always formed by the action of the excess of zinc 



