16. A solution is made by dissolving 25 g of NaCl in enough water to make 1.0 L of solution. Assume the density of the solution is 1.0 g/cm3. Calculate the molarity and molality of the solution.

Respuesta :

Answer:

The molarity will be "0.43 M" and molality will be "0.43 m".

Explanation:

Given that:

mass of NaCl,

= 25 g

Volume of solution,

= 1 L

Density of solution,

= 1 gm/cm³

Now,

The weight of solvent will be:

= [tex]Volume\times density[/tex]

= [tex]1\times 1[/tex]

= [tex]1 \ kg[/tex]

The mole of NaCl will be:

= [tex]\frac{mass}{Molar \ mass}[/tex]

= [tex]\frac{25}{58.44}[/tex]

= [tex]0.43[/tex]

hence,

The molarity will be:

= [tex]\frac{number \ of \ mole}{Volume \ of \ solution}[/tex]

= [tex]\frac{0.43}{1}[/tex]

= [tex]0.43 \ M[/tex]

The molality will be:

= [tex]\frac{mole \ of \ solute}{Weight \ of \ solvent}[/tex]

= [tex]\frac{0.43}{1}[/tex]

= [tex]0.43 \ m[/tex]