On addition of $1 \, mL$ solution of $10\% \, NaCl$ to $10 \, mL$ gold sol in the presence of $0.25 \, g$ of starch,the coagulation is just prevented. What is the gold number of starch?

The gold numbers of gelatin, haemoglobin and sodium acetate are $5 \times 10^{-3}$, $5 \times 10^{-2}$ and $7 \times 10^{-1}$, respectively. The protective actions will be in the order

Most suitable salt which can be used for efficient clotting of blood will be :-

$A$ $10^{-3} \ M$ solution of detergent $(C_{12}H_{25}SO_4^-Na^+)$ forms a colloidal sol. In $1 \ mm^3$ of the solution,there are on average $10^{13}$ colloidal particles. How many ions are present in one colloidal particle (micelle)? $(N_A = 6 \times 10^{23})$

The blue color of the sky is due to $.....$.

The charge on $As_2S_3$ sol is due to the adsorbed