Question

1.00 mL solution containing 0.24 $\mu Ci$ of tritium is injected into a dog's bloodstream. After a period of time to allow the isotope to be dispersed, a 1.00 mL sample of blood is drawn. The radioactivity of this sample is found to be 0.04 $\mu Ci/mL$. What is the total volume (in mL )of blood in the dog?

• A. 3
• B. 6
• C. 12
• D. None of these

Answer 1

The correct option is B 6

Let the total volume of blood in the dog be V mL.
Hence, $0.04\mu Ci/mL=\frac{0.24\mu Ci}{VmL}$
$V=6mL$.
Thus, the volume of blood in the dog is 6 mL.