Haughton — Notes on Netvtonian Chemistry. 637 
or, substituting for />t, /xi, from equation (1)', (2)', and using the 
proper units — 
Energy of position = 2(1+ fBio^). 
Energy of motion = - (1 + yScoj^). 
Total energy before collision =(1 + /Soii^). 
After collision we have — 
Energy of position = 2ix' j 
Energy of motion = - {aP + pm"^) w'^ ; 
or, introducing the proper units, and substituting for fx! from (3)' — 
Energy of position = 2 ^'^t 
Energy of motion = - ^'^ '■> 
or, total energy after collision = ^'^ j 
and finally, |l + ^(o^^ _ ^±1 = A, (5) 
represents the loss or gain of energy, when a molecule of hydrogen 
and a molecule of chlorine combine to form two molecules of hydro- 
chloric acid. 
When one gram of hydrogen combines with 35|- grams of chlorine 
the quantity of heat given out is sufficient to raise 22,000 grams of 
water 1° C.^ If, therefore, represent the number of molecules in 
one gram of hydrogen, the coefficient A, in equation (5) may be re- 
placed as follows : — 
22000 
A = — , 
because A represents the energy lost by one molecule of hydrogen 
combining with one molecule of chlorine. Equations (4) and (5) thus 
become 
(;8 + l)o>'=/5(l+^co0, (4y 
i.,V-^<»-^. (ay 
1 Thomsen. 
