contestada

How many moles of sodium chloride (NaCl) solute are in 155 grams of an 85.5 percent by mass solution?

Respuesta :

Willchemistry
85.5 percent by mass = 85.5 / 100 = 0.855

155 g x 0.855 => 132.525 g ( mass of solute )

Molar mass NaCl = 58.44 g/mol

number of moles:

n = mass of solute / molar mass

n = 132.525 / 58.44

n = 2.27 moles of NaCl

hope this helps!
EjerciciosFyQ
Our solution has 85.5 g of solute in 100 g of solution:

[tex]155\ g\ solution\cdot \frac{85.5\ g\ NaCl}{100\ g\ solution} = 132.52\ g\ NaCl[/tex]

The molecular mass of NaCl is: 23 + 35.5 = 58.5 g/mol.

[tex]132.52\ g\ NaCl\cdot \frac{1\ mol}{58.5\ g} = \bf 2.26\ mol\ NaCl[/tex]