Question

How many grams of NaCl in 50 mL of 0.75 M NaCl solution?

Answer 1

Molarity,

We have,
Molarity of NaCl solution = 0.75 M
Volume of NaCl solution = 50 ml or, 0.05 l

Have to find the amount of NaCl in grams.
Let the amount of NaCl = x g

Now,
As we know that,
$molarity = \frac{(mass \: of \: the \: solute)}{(volume \: of \: the \: solvent)}$
And the volume should be in liters.

So, 0.75 = x/0.05
or, 0.75 = x/(1/20)
or, 0.75 = 20x
or, x = 0.0375 g

Therefore 0.0375 g of NaCl are present in 3M of NaCl solution.

That's it
Hope it helped (≧▽≦)