Concentrated hydrochloric acid has 37.5% of HCl in mass and density of 1.2 g/cm3. What volume (in mL) of concentrated hydrochloric acid should be used to prepare 7 L of a 0.8 mol/L HCl (aq) concentration solution?

First determine the molarity of the concentrated HCl.

That is 1000 mL x 1.2 g/mL x 0.375 x (1 mol/36.5) = ? mols/L = M

Then mL1 x M1 = mL2 x M2
7000 mL x 0.8 M = mL2 x approx 12 M
Note: That 12 M is an estimate.

Thank u so much :)

To find the volume of concentrated hydrochloric acid needed, we first need to calculate the amount of HCl needed for the 7 L solution.

Step 1: Calculate the amount of HCl needed in moles:
The concentration of the solution is given as 0.8 mol/L, and the volume of the solution needed is 7 L.
moles of HCl = concentration × volume
moles of HCl = 0.8 mol/L × 7 L
moles of HCl = 5.6 mol

Step 2: Calculate the mass of HCl needed:
The molar mass of HCl is approximately 36.5 g/mol.
mass of HCl = moles of HCl × molar mass of HCl
mass of HCl = 5.6 mol × 36.5 g/mol
mass of HCl = 204.4 g

Step 3: Calculate the mass of concentrated hydrochloric acid needed:
The concentrated hydrochloric acid has a concentration of 37.5% and a density of 1.2 g/cm3.
mass of concentrated HCl = mass of HCl / (% concentration / 100)
mass of concentrated HCl = 204.4 g / (37.5 / 100)
mass of concentrated HCl = 204.4 g / 0.375
mass of concentrated HCl = 545.07 g

Step 4: Calculate the volume of concentrated hydrochloric acid needed:
volume of concentrated HCl = mass of concentrated HCl / density
volume of concentrated HCl = 545.07 g / 1.2 g/cm3
volume of concentrated HCl = 454.22 mL

Therefore, approximately 454.22 mL of concentrated hydrochloric acid should be used to prepare 7 L of a 0.8 mol/L HCl (aq) concentration solution.

To solve this problem, we need to use the formula:

Molarity (M) = moles (mol) / volume (L)

We know that we want to prepare a 7 L solution with a concentration of 0.8 mol/L. Therefore, we can rearrange the formula to solve for the moles of HCl:

moles (mol) = Molarity (M) × volume (L)

moles (HCl) = 0.8 mol/L × 7 L
moles (HCl) = 5.6 mol

Now, we need to calculate the amount of HCl in grams. Since concentrated hydrochloric acid has a concentration of 37.5% of HCl in mass, we can use this information to find the amount of HCl:

mass (g) = concentration (%) × volume (mL) × density (g/cm³)

We need to solve for the volume (mL), which is the quantity we need to determine. Rearranging the formula for volume, we get:

volume (mL) = mass (g) / (concentration (%) × density (g/cm³))

Let's calculate the mass of HCl:

mass (HCl) = 37.5% × volume (mL) × density (g/cm³)

To determine the volume of concentrated hydrochloric acid needed, we need to substitute mass (HCl) with the number of moles of HCl just calculated and solve for volume (mL):

37.5% × volume (mL) × density (g/cm³) = moles (HCl) × molar mass (HCl)
volume (mL) = (moles (HCl) × molar mass (HCl)) / (37.5% × density (g/cm³))

Now, let's substitute the values:

volume (mL) = (5.6 mol × 36.461 g/mol) / (0.375 × 1.2 g/cm³)
volume (mL) = 206.0976 g / (0.45 g/cm³)
volume (mL) = 457.995 mL

Therefore, approximately 458 mL of concentrated hydrochloric acid should be used to prepare 7 L of a 0.8 mol/L HCl (aq) concentration solution.