Question

Express 2.5M NaCl as a percent solution. what is the molar concentration of a 10% NaCl solution?

Answer 1

What kind of percent is that? percent w/v
2.5M means 2.5 moles NaCl/L soln.
grams = moles x molar mass
So yo have grams/L, convert to g/100 mL and that is percent NaCl.

10%w/v means 10g NaCl/100 mL which makes it 100 g NaCl/L soln.
100 g = ? moles. moles = g/molar mass so that is the molarity.

Answer 2

1.7M