Molecular formula of starch can be represented as ${\left({\mathrm{C}}_6{\mathrm{H}}_{10}{\mathrm{O}}_5\right)}_{\mathrm{n}}$. If the gold number of one such starch is 6.48 and 0.01 millimoles of this starch is required to be added in 10 ml of red gold sol to just prevent coagulation by adding 1 ml of 10% sodium chloride solution, then the value of ‘n’ is