Then, determine the final volume needed to dilute 20.0 ml of 1.00 M NaOH to 0.25 M. Next, find the volume of water which needs to be added. Finally, determine the moles and the mass in grams of NaOH in the solutions.
Final volume formula is Vf= mi/mf
20 ml=1.00/0.25=80 ml 80-20= 60 ml Vf-vi to get water
Is this right? I am having trouble converting
Looks ok to me for the dilution but mols and grams you didn't do.
Do I use the 60 ml to convert to mols and grams ?
60ml(0.25/.06) 0.150 mols how would I get grams
For the 20 mL of 1.00 M NaOH you have mols = M x L = 0.020 x 1.00 = 0.020 mols and grams = mols x molar mass.
diluted solution (0.25M) you have the same, don't you? You added 20 mL of 1.00 M NaOH to 60 mL H2O so you added 0.02 mols for that dilution. Yes the concentration changed because you put that same 0.02 mols in a larger volume of 80 mL and 0.02mols/0.08L = 0.25M. Of course grams is same also.
Yes, you are on the right track. To determine the final volume needed to dilute 20.0 ml of 1.00 M NaOH to 0.25 M, you can use the formula:
Vf = (Mi/Mf) * Vi
where Vf is the final volume, Mi is the initial molarity, Mf is the final molarity, and Vi is the initial volume.
In this case, Mi is 1.00 M, Mf is 0.25 M, and Vi is 20.0 ml.
Plugging in these values, we have:
Vf = (1.00 M / 0.25 M) * 20.0 ml
Vf = 4 * 20.0 ml
Vf = 80.0 ml
So, the final volume needed to dilute 20.0 ml of 1.00 M NaOH to 0.25 M is 80.0 ml.
To find the volume of water that needs to be added, you can subtract the initial volume (Vi) from the final volume (Vf):
Volume of water = Vf - Vi
Volume of water = 80.0 ml - 20.0 ml
Volume of water = 60.0 ml
Therefore, you need to add 60.0 ml of water to the 20.0 ml of 1.00 M NaOH to achieve a final volume of 80.0 ml at a concentration of 0.25 M.
For determining the moles and mass of NaOH in the solution, you need to use the concentration (M) and the volume (V) of the solution, along with the molar mass of NaOH.
Moles of NaOH = M * V
Mass of NaOH = Moles of NaOH * Molar mass of NaOH
Given that the concentration of the solution is 0.25 M and the final volume is 80.0 ml, we can calculate the moles of NaOH:
Moles of NaOH = 0.25 M * 80.0 ml
Moles of NaOH = 20.0 mmol
To find the mass of NaOH, we need to know its molar mass. The molar mass of NaOH is approximately 23.0 g/mol for Na, 16.0 g/mol for O, and 1.0 g/mol for H. Adding these values together, we find the molar mass of NaOH to be approximately 40.0 g/mol.
Mass of NaOH = Moles of NaOH * Molar mass of NaOH
Mass of NaOH = 20.0 mmol * 40.0 g/mol
Mass of NaOH = 800.0 mg
Therefore, in the final solution, there are 20.0 mmol (or 0.020 mol) of NaOH, which corresponds to a mass of 800.0 mg.