<prompt> One gram of hemoglobin contains how much iron -2 mg3.4 mg5 mg6 mg  <response>: Ans. is b i.e., 3.4 mg o One gram of hemoglobin contains 334 mg of iron.o Normally. 100 ml of blood contains 15 gm of hemoglobin and about 50 mg of iron 3.34 15.o So, if 100 ml of blood is lost from the body, there is a loss of about 50 mg of iron,o In females, during every menstural cycle, about 50 ml of blood is lost by which 25 mg iron is lost. 