Question

How much water would you need to form 2.00 L of a 1.00 M solution of NaCl? NaCl has a molecular weight of 57.4 g/mol and a density of 2.16 g/mL.

A) 1.89 L

B) 1.95 L

C) 2.00 L

D) 2.05 L

Why is the answer B?

Answer 1

1.00M, 2.001 Nach solution molarity = moles of solute Volume of solution moles of Nach 2 litre = 2 mol Nach moles of Nach in 2.00L of 1.00M of Nall 2 x molar mans Nach = ~ mals of 2 mol = 2 x 58.45 gm = 116.9 → density of Nacl = 2.16 g/ml density = mare volume 116.9 gm 2.16 gm /mL Volume = man density Volume = 54.12 ml .. volume of Nach = 54.12 m2 of solution Total volume - volume of water (solvent) + Volume of solute (NaCl) + 54.12 mL 2 litre = volume of water Volume of water = 2 litre - s4.12 m2 = (2000 ml) - 154.12 ml) = 1945.88 ml ř 1.946 litre ł 1.95 litre