what is the molarity of the solution which contains 5.0g of NaOH(formar weight=40g/mole)dissolved in water to make 200 ml of soluitons?
moles = grams/molar mass
molarity = mols/L
Post your work if you get stuck.
m=mols/L
first, get the no. of moles.
n=wt/mw
where n = no. of moles
wt = weight
mw = molecular weigth
n = 5.0g / 40 g/mol
cancel the grams, so the left unit is mol.
Ans. n=0.125mol
You can now get the molarity of the solution,
m = n/L
where m = molarity
m= 0.125mol / 200ml
*conversion:
1L=1000ml
200ml x 1L/1000mL
==> 0.2L
you can now solve the molarity
m= 0.125mol / 0.2L
ANS: m = 0.625mol/L
To find the molarity of a solution, you need to know the number of moles of the solute (NaOH) and the volume of the solution.
Step 1: Calculate the number of moles of NaOH:
Moles = mass / molar mass
Given that the mass of NaOH is 5.0g and the molar mass is 40g/mole:
Moles = 5.0g / 40g/mole
Step 2: Calculate the volume of the solution in liters:
Volume = 200 ml = 200/1000 L (since 1 L = 1000 ml)
Step 3: Calculate the molarity:
Molarity = Moles / Volume
Molarity = (5.0g / 40g/mole) / (200/1000 L)
Simplifying the calculation:
Molarity = (5.0g / 40g/mole) * (1000 L / 200)
Molarity = 0.25 moles / 1 L
So, the molarity of the solution is 0.25 M.