cM = n/V
15 ml = 0,015 l
n tiosulfat = 0,015*0,2 = 0,003 moli tiosulfat
1 mol iod..........2 moli tiosulfat
x.........................0,003 moli tiosulfat
x = 0,0015 moli I2
1 mol bicromat........3 moli I2
y.................................0,0015 moli I2
y = 0,0005 = 5*10^(-4) moli K2Cr2O7
M bicromat = 298
m K2Cr2O7 = 5*10^(-4)*298 = 0,149 g K2Cr2O7