Question

Following experiment is designed to determine calcium content in the blood. Read the experiment and answer the questions at the end of it.
Calcium oxalate $\left(Ca{C}_2{O}_4\right)$ is insoluble in water. For this reason, it can be used to determine the amount of $C{a}^{2+}$ ions in fluids such as blood. The calcium oxalate isolated from blood is dissolved in acid and titrated against a standardized $KMn{O}_4$ solution.

Calcium content expressed in ppm is $250$.

• A. True
• B. False

Answer 1

The correct option is A True

$25$ mL of $1\times {10}^{-3}M{Mn{O}_4}^{-}$ $=25$ mL of $5\times {10}^{-3}N{Mn{O}_4}^{-}$
$=0.125$ milliequivalents of ${Mn{O}_4}^{-}$
$=0.125$ milliequivalents of $Ca{C}_2{O}_4$
$=0.125$ milliequivalents of $C{a}^{2+}$
$=0.125\times 20$ mg of $C{a}^{2+}$ in $10$ mL
$=0.250$ mg/mL $=0.250$ g/L $=250$ ppm