How do you prepare a 2.5 molal NaOH solution?

Answer 1

Actually molal is moles of solute per kg of solvent, thus you don't need a volumetric flask.

The molecular weight is 40.
So you need 2.5*40= 100 g NaOH per 1 kg of water.
If you really want to prepare approximately 1 L of solution, then use an appropiate beaker and weigh 1 kg of water. Then add to that 100g of NaOH, mix and you're done.

The density of water is approximately 1 g/mL. So if you want to prepare V mL of solution then you need approximately V g of water. However, in order to be more accurate, you should use an appropriate beaker to weigh the amount of water and then using the equation
molality = mass (solute)*1000 /(MW(solute)* mass (solvent)) with mass(solvent) and mass(solute) expressed in g you find how much solute you need.

E.g. if you want approximately 100 mL solution, then you should weigh 100 g water (the final volume will be a bit different than 100 mL but here we are interested in the accuracy of mole/kg solvent and not V solution). Then you need to add to the water
2.5 =1000 *mass/40*100 =>
mass =10 g NaOH

Answer 2

the formulation for molality is m=G / (Mr * kg solvent) the place G=mass of the substance in grams, Mr=molecular weight of the factors, kg solvent= mass of solvent (in basic terms solvent no longer answer) in kilograms. in view that Mr for NaOH= 40 g/mol, we are able to prepare 2.5 molal of NaOH with the help of including one hundred grams of NaOH to a million L (=a million kg as water density=a million g/cm^3) of water(as a solvent)

Answer 3

Take 2.5 moles NaOH and mix with 1 L of H20.

Answer 4

use this following for any molar solution question.

M.W = molecular weight of compound to be put in solution
A = molarilty of solution or number of moles in solution
B = number of mL of solution you have to make.

Weight of compound needed = M.W x a x B / 1000

Now with the weight but into a volumetric flask and dilute with water until it reaches B.