Question

How many grams of NaCl are contained in 0.50 L of a 4.20 M solution?

58.44 g NaCl

245.5 g NaCl

122.7 g NaCl

173.6 g NaCl

Answer 1

Answer:

The answer to your question is the third option: 122.7 g of NaCl

Explanation:

Data

mass of NaCl = ?

molecular mass of NaCl = 23 + 35.5 = 58.5

volume = 0.50 l

concentration = 4.20 M

Formula

$Molarity = \frac{moles}{volume}$

     Moles = Molarity x volume

Process

1.- Substitute the data given to find the moles of NaCl

     Moles = 4.20 x 0.5

     Moles = 2.1

2.- Calculate the grams of NaCl using proportions

     58.5 g of NaCl ----------------- 1 mol

        x                     ----------------  2.1 moles

      x = (2.1 x 58.5) / 1

3.- Result

      x = 122.7 g of NaCl