π = mRT (m = molarity, R = 0.082 L atm/mol. K, T = 25°C = 298K ) M = m =
π
RT
=
5×10−3
0.082×298
= 2 × 10−4 M =
w
m×V
m =
w
M×V
m =
10
2×10−4
= 5 × 104 Each glucose unit (mw = 180) Bonded to the starch chain with bss of 1 H2O (mm = 18) giving a effective molecular mass = 180 - 18 = 162 So approximate average number of glucose =