How many grams of NaOH are needed to prepare 250 mL of 0.205 M NaOH?

1 Answer
Feb 28, 2017

A bit over 2*g...............

Explanation:

"Concentration" = "Moles of solute (moles)"/"Volume of solution (L)"

Thus "Concentration"xx"volume"="moles of solute"

0.205*mol*cancel(L^-1)xx0.250*cancelL="Moles of solute"

=0.0513*mol, an answer in moles as required.

And thus "mass of NaOH" = "moles "xx" molar mass"

=0.0513*cancel(mol)xx40.0*g*cancel(mol^-1)

=2.05*g