a solution of sulfiric acid is 40% H2SO4 by mass and it has a density of 1.30g/ml at 25 degrees Celcious. the molarity of this solution is....?
40% H2SO4 means 40 g H2SO4/100 g solution
Convert 40 g to moles. moles = grams/molar mass.
Convert 100 g soln to volume using the density, then M = moles/L of soln.
To determine the molarity of the sulfuric acid solution, we will first need to convert the given information into relevant units.
Step 1: Calculate the mass of the solute (H2SO4):
Assuming we have 100 grams of solution, 40% of that would be the mass of the solute (H2SO4):
Mass of H2SO4 = 40% × 100 g = 40 g
Step 2: Calculate the volume of the solution:
The density of the solution is given as 1.30 g/mL. Density is defined as mass divided by volume, so we can rearrange the equation to solve for the volume:
Volume of solution = Mass of solution / Density
Since we assumed that we have 100 grams of solution, we can substitute these values into the equation:
Volume of solution = 100 g / 1.30 g/mL ≈ 76.93 mL
Step 3: Convert the volume in mL to volume in liters:
To convert mL to L, divide the volume in mL by 1000:
Volume of solution = 76.93 mL ÷ 1000 = 0.07693 L
Step 4: Calculate the molarity of the solution:
Molarity (M) is defined as moles of solute divided by the volume of the solution in liters. The molar mass of sulfuric acid (H2SO4) is:
H: 1.0079 g/mol x 2 = 2.0158 g/mol
S: 32.06 g/mol
O: 15.999 g/mol x 4 = 63.996 g/mol
Molar mass of H2SO4 = 2.0158 + 32.06 + 63.996 = 98.07 g/mol
To determine the moles of solute, divide the mass of the solute by its molar mass:
Moles of H2SO4 = Mass of H2SO4 / Molar mass of H2SO4
Moles of H2SO4 = 40 g / 98.07 g/mol ≈ 0.4083 mol
Now we can calculate the molarity:
Molarity = Moles of H2SO4 / Volume of solution in liters
Molarity = 0.4083 mol / 0.07693 L ≈ 5.31 M
Therefore, the molarity of the sulfuric acid solution is approximately 5.31 M.