if i want to find the molarity of a solution that is:
5mL of a 3.521 x 10^-5 M solution,
and filled to the 50mL line with ethanol,
would this be:
(3.521 x 10^-5)(.04L ethanol)?
YOu diluted it by a factor of ten, so it is 1/10 the original molarity.
Molarity=molessolute/litersSOLUTION
So your answer is off.
Molality uses kg solvent in the denominator. Make some flashcards and memorize those.
well, how many moles do you have?
5 *10^-3 L * 3.521 * 10^-5 moles/L
= 17.605 * 10^-8 moles
That is in 50 *10^-3 Liters of solution
so
17.605 *10^-8 moles / 50*10^-3 L
= .3521 *10^-5 moles/L
= 3.521 * 10^-6 M
In other words we diluted it ten to one with ethanol
I mean 9 to one with ethanol.
To find the molarity of a solution, you need to know the amount of solute (in moles) and the volume of the solution (in liters).
In this case, you are given that you have a 5 mL sample of a 3.521 x 10^-5 M solution. The molarity (M) of a solution is equal to moles of solute divided by liters of solution.
First, let's calculate the moles of solute:
moles of solute = Molarity x Volume (in liters)
moles of solute = (3.521 x 10^-5 M) x (5 mL / 1000 mL/L)
moles of solute = (3.521 x 10^-5 M) x (0.005 L)
moles of solute = 1.7605 x 10^-7 moles
Next, let's calculate the volume of the solution:
volume of solution = sample volume + final volume
volume of solution = 5 mL + 50 mL
volume of solution = 55 mL = 0.055 L
Finally, let's calculate the molarity of the solution:
Molarity = moles of solute / volume of solution
Molarity = (1.7605 x 10^-7 moles) / (0.055 L)
Molarity ≈ 3.201 x 10^-6 M
So, the molarity of the solution is approximately 3.201 x 10^-6 M.
To summarize the process:
1. Convert the given volume of the solution to liters.
2. Calculate the moles of solute using the given molarity and the converted volume.
3. Determine the total volume of the solution by adding the given sample volume to the final volume.
4. Divide the moles of solute by the volume of the solution to find the molarity.