Concentrated NaOH(aq) (NaOH MM = 40.00 g/mol) is usually available at a concentration of 42.30 by mass% and has a density of 1.230 g/mL. What is its molar concentration (molarity)?
To calculate the molar concentration (molarity), we need to find the number of moles of NaOH in 1 liter (1000 mL) of the solution.
First, we need to find the mass of NaOH in the solution:
Mass of NaOH = 42.30% * 1000 mL * 1.230 g/mL = 520.23 g
Next, we need to find the number of moles of NaOH:
Number of moles = mass / molar mass = 520.23 g / 40.00 g/mol = 13.01 mol
Finally, we can calculate the molar concentration:
Molarity = moles / volume = 13.01 mol / 1 L = 13.01 M
Therefore, the molar concentration of the NaOH solution is 13.01 M.