1107 
Bromine and methyl-alcohol. 
| 
; Amount of 
Quality of Light eae Bromus Venen | Volume of solution. 
in grams. 
a) Sunlight 150’ 0.06527 0.01154 | 5 c.c. methyl-alcohol and 
eines 150’ Do 0.06205 \ 10 cc. bromine water. 
b) Sunlight 280’ Do 0.00903 | 10c.c. methyl-alcohol and 
eee 280 | Do 0.05420 { 10 cc. bromine water. 
c) Diffused light 155’ Do | 9.01998 |) sec methyl-alcohol and 
ee 155! Do 0.06210 \ 10 ec. bromine water. 
d) Diffused light 285’ Do 0.01610 10 c.c. methyl-alcohol and 
eae 283/ Do 0.05412 { 10 ec. bromine water. 
it has also been observed that the action of bromine on methyl 
alcohol is also accelerated by light. Price (Zeit. Phys. Chem. 1898, 
27, 474) has shown that persulphates slowly liberate iodine from 
a solution of potassium iodide. 
Now it has been found out that persulphates can slowly liberate 
bromine from a solution of bromides and that in presence of light 
the action is much more rapid than in darkness 
2 NaBr + Na,S,O, = 2 Na,SO, + Br,. 
Sodium persulphate and Potassium bromide. 
— ——— —— 
Time of | Amount of 
Quality of Light. exposure. bromine liberated: Volume of solution. 
1) Sunlight 300’ | 0.00508 |) 25 cc. N KBr and 10c.c. 
Marknese 300’ | 0.00406 | | 10 sodium persulphate. 
2) Sunlight 420’ | 0.00687 
Darkness 420’ | 0.00575 | 23 
3) Sunlight 480 ___|____0.00923 | 5 cc. N KBr and 20c.c. 
Darkness 480’ 0.00801 | | a sodium persulphate, 
4) Diffused light 540’ | 0.00776 | 25 cc. N KBr and 10 ec. 
Darkness 540 | Ss 0.00712 | {9 Sodium persulphate. 
5) Diffused light 620’ | 0.00916 25 c.c. N KBr and 10c.c. 
Darkness 620’ 0.00849 na sodium persulphate. 
