OXIDATION OF SUCROSE BY POTASSIUM PERMANGANATE, 220 
4. In the fourth experiment the concentrations of both 
sucrose and potassium permanganate were halved. 
Concentration of sulphuric acid ‘58 N. Concentration of man- 
ganese sulphate ‘017 N. (a) 0365 N.; (b) 0056 N. Temp. 15°C. 
t n a (a-x) (b—2x) ky ky 
ae 151 es: 70365  :0056 me ae 
5 18:0 ‘O01 0349"; 0040" -0672 000188 
eels 9 “0021 » --0344 0035-0671 "000190 
11 =. 20°3 "0029 =:0336 = 0027) = -0676 = -000190 
13-209 70033-0332 = :0023:-«-:0677 = -000198 
20 22:0 0039 «0326 «©0017-0596 = -000175 
oc 25:0 70056 = :0309 
If this reaction is one of the second order, the velocity 
constant may be written 
1 a-x) b 
i — 7166) . log. ae = 
so that t, the time taken for any definite amount of the 
reaction to proceed may be written 
1 a—x)b 
(geby eas ae a 
From this equation it can be calculated that if a, the 
concentration of sucrose is halved, the time the reaction 
takes to proceed half-way should roughly double itself; if 
b the concentration of potassium permanganate is halved, 
the time taken to proceed half-way should remain the 
same; and if both a and b are halved the time taken 
to proceed half-way should be roughly double the time 
taken before dilution. 
That this is the case with the reaction in question is 
shown by the following figures collected from the foregoing 
tables :-— 
Concentration of Concentration of Time taken to 
sucrose (a). pot. permg. (0). proceed half-way. 
‘0731 0113 54 mins. 
°0365 “OLLS 1, Rs 
‘0731 "0057 5 
9 
-0365 0057 iG 
