4 L of 0.02 M aqueous solution of NaCl wasdiluted by adding one litre

1.	4 L of 0.02 M aqueous solution of NaCl wasdiluted by adding one litre of water. Themolality of the resultant solution is01)a) 0.004b) 0.008c) 0.012d) 0.016
Answer» First of all density of 0.02M aq. soln. of NaCl should be known/given,so that mass of soln. will be known. If density assumed to ne one(which is actually greater than one):then ; no. of moles of NaCl in 4L of soln.=0.08 mole. Mass of 4+1=5L of water=5kg. So molality=0.08/5=0.016 mols per kg.

4 L of 0.02 M aqueous solution of NaCl wasdiluted by adding one litre of water. Themolality of the resultant solution is01)a) 0.004b) 0.008c) 0.012d) 0.016

Answer»

First of all density of 0.02M aq. soln. of NaCl should be known/given,so that mass of soln. will be known.

If density assumed to ne one(which is actually greater than one):then ;

no. of moles of NaCl in 4L of soln.=0.08 mole.

Mass of 4+1=5L of water=5kg.

So molality=0.08/5=0.016 mols per kg.