<prompt> The concentration of sodium ions in the standard WHO oral rehydration Solution is:40 m molesL60 m molesL90 m molesL110 m molesL  <response>: Concentration of Na is 90 mmolL in standard WHO-ORS whereas it is 75 mmolL in New formula ORS. NEW FORMULA ORS contains :- Na - 75 mM k - 20mM Cl- - 65mM Glucose - 75mM Citrate - 10mM Total - 245mOsmL 