I've been working on this problem for hours and cant figure it out. I know it should be simple, but I'm stuck...

The question is...

Describe how to prepare 1.00L of a 1.0% (w/v) NaOH from a 2.0 M NaOH. *I need to figure out how many ml of the stock solution is needed.

So far I know
1. 1.0% (w/v) means 1g NaOH per 100 ml.

2. 2 M NaOH = 79.994 g NaOH

I would convert 1.0% w/v to M.

1 g/100 mL = 10 g/1000 mL.
10 g = ? mols; that's 10/40 = 0.25 mols and that in 1 L = 0.25M, then apply the dilution formula of
c1v1 = c2v2
0.25*1000mL = 2.0*v2mL
solve for v2.

Okay...

Where did you get 10/40? Also, where would the 79.994g of NaOH come in?

mols NaOH = grams NaOH/molar mass NaOH.

Sorry I didn't spell that out.

Here is what I came up with, but not sure if it is correct.

2 moles of NaOH = 79.994g NaOH

79.994g/1L * 1L/1000mL * 100mL/1g = 7.9

Baloney!

I worked the problem for you except for the last step. All you need to do is to solve for v2 and the answer will be in mL. You're to describe how to make it You take v2 mL of the stock solution, place in a 1.0 L volumetric flask, then add water to the mark and mix thoroughly.

Okay. Thanks for your help.

To prepare 1.00L of a 1.0% (w/v) NaOH solution, you can follow these steps:

1. Calculate the total amount of NaOH needed for the desired concentration:
Since the desired concentration is 1.0% (w/v) and you have 1.00L of solution, you can calculate the amount of NaOH required using the formula:
Amount of NaOH (in grams) = (1.0% / 100) * 1000 mL = 10 grams

2. Convert the amount of NaOH to moles by using the molar mass of NaOH:
The molar mass of NaOH is 22.99 g/mol for Na, 16.00 g/mol for O, and 1.01 g/mol for H.
So, the molar mass of NaOH is 22.99 + 16.00 + 1.01 = 39.99 g/mol.
The number of moles of NaOH required is:
Moles of NaOH = Mass of NaOH / Molar mass of NaOH = 10 g / 39.99 g/mol = 0.250 mol

3. Use the given concentration of the stock solution to determine the volume needed:
The stock solution has a concentration of 2.0 M, which means it contains 2.0 moles of NaOH per 1.00 liter of solution.
To find the volume of the stock solution needed, use the formula:
Volume of stock solution (in liters) = Moles of NaOH needed / Stock solution concentration
Volume of stock solution = 0.250 mol / 2.0 M = 0.125 L = 125 mL

Therefore, you will need to measure out 125 mL of the 2.0 M NaOH stock solution to prepare 1.00L of a 1.0% (w/v) NaOH solution.