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