Amount of ${\text{O}}_2$ normally carried by $100\text{ml}$ of pure human blood, is

Under normal physiological conditions, $100\text{ml}$ of oxygenated (pure) human blood contains about $15\text{g}$ of hemoglobin. Since each gram of hemoglobin can bind up to approximately $1.34\text{ml}$ of oxygen, the total oxygen content carried is around $15\times 1.34\approx 20\text{ml}$. Out of this, around $5\text{ml}$ of oxygen is delivered to the tissues under normal resting conditions.