Answer:
The correct answer is m= mol solute kg soivent
Explanation:
Molality is a measure of concentration, which indicates the moles of solute (in this case sodium hydroxide) in 1kg of solvent .
In this case:
0,800 kg water-----0,400 mol NaOH
1 ,000 kg water ---x=(1 ,000 kg water x 0,400 mol NaOH)/0,800 kg water
x=0,5 mol NaOH---> <em>The solution is 0,5 molal (0,5 m)</em>
