Question

What is the molarity (M) of .5 liter of a solution that has 205 g of NaCl dissolved in it?

Answer 1

Answer:

Molarity = 7 mol / L

Explanation:

Since the mass of NaCl and it's volume has been given we can find the molarity by using the formula

$C = \frac{m}{M \times v}$

where

C is the molarity

m is the mass

M is the molar mass

v is the volume

From the question

v = 0.5 L

m = 205 g

We must first find the molar mass and then substitute the values into the above formula

M( Na) = 23 , M( Cl) = 35.5

Molar mass of NaCl = 23 + 35.5 =

58.5 g/mol

So the molarity of NaCl is

$C = \frac{205}{0.5 \times 58.5} \\ C = \frac{205}{29.25}$

C = 7.00854

We have the final answer as

Molarity = 7 mol / L

Hope this helps you