The forensic technician at a crime scene has just prepared a luminol stock solution by adding 19.0 g
of luminol into a total volume of 75.0 mL
of H2O
.
What is the molarity of the stock solution of luminol?
To find the molarity of the stock solution of luminol, we first need to calculate the number of moles of luminol in the solution.
First, we need to convert the mass of luminol from grams to moles using the molar mass of luminol, which is 177.18 g/mol.
Number of moles of luminol = 19.0 g / 177.18 g/mol
Number of moles of luminol = 0.107 mol
Next, we need to calculate the volume of the stock solution in liters.
Volume of stock solution = 75.0 mL / 1000 mL/L
Volume of stock solution = 0.075 L
Now, we can calculate the molarity of the stock solution of luminol using the formula:
Molarity (M) = Number of moles / Volume of solution in liters
Molarity = 0.107 mol / 0.075 L
Molarity = 1.43 M
Therefore, the molarity of the stock solution of luminol is 1.43 M.