In the preparation of one liter of 2.5 M HCl solution, what is the volume of HCl
concentrated (37% w / w, d = 1.19 g / ml) to be used?
Concentrated HCl is commonly 11.8M.
So you are diluting it 11.8/2.5 times, or 4.72 times. That means, you need one part conc HCl, and 3.72 parts water.
What is one part? 1000ml/4.72=2.118ml
so measure 2.2118ml*3.72=788.14 ml water, and add 2.118 ml of conc HCl slowly, stiring, wearing googles and gloves. Always do this under the vent hood, and always add acid to water.
To calculate the volume of concentrated HCl required to prepare a 2.5 M solution, you need the molarity and density of the concentrated HCl solution.
Let's break down the steps to solve this problem:
Step 1: Understand the given information.
- Molarity of the desired solution: 2.5 M
- Percentage concentration of the concentrated HCl solution: 37% w/w
- Density of the concentrated HCl solution: 1.19 g/ml
Step 2: Calculate the mass of HCl required.
To determine the mass of the concentrated HCl needed, we need to know the volume of the desired solution (1 L) and its molarity (2.5 M). We can use the formula:
Molarity = Moles of solute / Volume of solution in liters
To calculate the moles of solute (HCl):
Moles of solute = Molarity × Volume of solution in liters
Since we want to prepare 1 L of 2.5 M HCl solution, the moles of HCl can be calculated as:
Moles of HCl = 2.5 mol/L × 1 L = 2.5 mol
Step 3: Calculate the mass of HCl required using the formula:
Mass of solute = Moles of solute × Molar mass
The molar mass of HCl is:
Molar mass of HCl = (1 × Atomic mass of H) + (1 × Atomic mass of Cl) = 1.01 g/mol + 35.45 g/mol = 36.46 g/mol
Thus, we can calculate the mass of HCl required:
Mass of HCl = 2.5 mol × 36.46 g/mol = 91.15 g
Step 4: Calculate the volume of the concentrated HCl required.
Using the density of the concentrated HCl solution, we can relate the mass and volume using the formula:
Mass = Volume × Density
Rearranging the formula to solve for volume:
Volume = Mass of HCl / Density
Plugging in the values:
Volume = 91.15 g / 1.19 g/ml ≈ 76.61 ml
Therefore, to prepare 1 L of 2.5 M HCl solution, you will need approximately 76.61 ml of concentrated HCl solution with a density of 1.19 g/ml.