Calculate how many moles of nacl would be necessary to prepare 100.0 ml of 0.517 m nacl solution.

So, molarity is defined as the number of moles of solute per liter of solution. In your case, a 0.77 M solution will contain 0.77 moles of sodium chloride, your solute, in 1.0 L of solution. 44 g NaCl