<prompt> 1 equivalent of Ca2 ion is equal to:10 gram20 gram30 gram40 gram  <response>: The concept of electrical equivalence is impoant in physiology because many of the solutes in the body are in the form of charged paicles. One equivalent eq is 1 mol of an ionized substance divided by its valence. One mole of NaCl dissociates into 1 eq of Na and 1 eq of Cl-. One equivalent of Na 23 g, but 1 eq of Ca2 40 g2 20 g. The milliequivalent meq is 11000 of 1 eq. Ref: Ganongs Review of Medical Physiology 23rd edition, Chapter 1. 