Question

How many grams of solute are dissolved in 125.0 mL of 5.00 M NaCl (MM = 58.45)?

Answer 1

Answer: 36.53g

Explanation:

First we need to find the amount of NaCl that dissolves in 1L of the solution that produced 5M of NaCl

Molarity = 5M

MM of NaCl = 58.45

Molarity = Mass conc (g/L) / MM

Mass conc. (g/L) of NaCl = Molarity x MM

= 5 x 58.45 = 292.25g

Next, we need to find the amount that will dissolve in 125mL(i.e 0.125L)

From the calculations above,

292.25g of NaCl dissolved in 1L

Therefore Xg of NaCl will dissolve in 0.125L of the solution i.e

Xg of NaCl = 292.25 x 0.125 = 36.53g.

Therefore 36.53g of NaCl will dissolve in 125mL of the solution