Kitty F.

# Mass of NaOH needed to make 500mL of 0.1M NaOH solution?

I'm working on a solutions lab and would like someone to look over my calculations please.

"What mass of solid NaOH is needed to make 500mL of 0.1M NaOH solution?"

My work:
Needed:  500mL solution with a final concentration of .1M

Na:  22.989 amu
O:   15.999 amu
H:   1.008 amu
=39.996 amu  (rounded to 40amu)
40 amu= 1 mole NaOH

To make one mole NaOH solution, dissolve 40 grams NaOH in 500mL of H2O.

mL to L conversion:
500/1000=.5
For .5L of 0.1M solution, we need 0.1M of solute.
0.1M of solute x 40 grams/Mole= 4 grams NaOH

The solution would be made by dissolving 4 grams NaOH in .5 Liters of H2O

## 2 Answers By Expert Tutors

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Understanding math via the real world.

Ayilumo J.

I think the answer should be 2 g not 4g
Report

11/15/15

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