A 7.83 g sample of NaCl is dissolved in 90.00 mL of ethyl alcohol solution. How do you calculate the molar concentration of the solution?
I suspect that your figures are wrong (please, I do realize that anyone can make a mistake; I know because I make plenty). Sodium chloride does not display much alcoholic solubility. Are you sure that the question specified ethanol not water?
If the solvent were ethanol,