Final answer:
The mEq/L of calcium is about twice that of sodium since calcium has a 2+ charge, resulting in twice the equivalents compared to sodium which has a 1+ charge.
Step-by-step explanation:
The question involves the concept of equivalents and the conversion of concentration units for ionic solutions. Since sodium has a +1 charge, one milliequivalent (mEq) is equal to one millimole of sodium. Calcium, having a charge of 2+, means that one milliequivalent of calcium is equal to 0.5 millimoles of calcium. The atomic weight of sodium is 23, and that of calcium is 40.
If two solutions have equal mg%, this means they have the same mass of the solute per volume of solution in milligrams per percent. However, milliequivalents take into account both the mass and the valence (charge) of the ions. So even though the solutions have the same milligrams per percentage, they will have different mEq/L concentrations because of the different charges on the sodium and calcium ions. The mEq/L of calcium would therefore be about twice that of sodium because each calcium ion carries twice the charge of a sodium ion.