A solution of hydrogen peroxide is 24.26% by mass and has a density of 1.11g/cm^3. the molarity of the solution?
7.54M
.273M
8.03M
8.37M
none of these
Take a liter of the stuff.
then mass is 1110 grams, of which 269 grams is H2O2.
Molarity= 269/(molmassH2O2*1)
The closest is the third. Check my math.
To determine the molarity of the hydrogen peroxide solution, we need to gather the necessary information and apply the appropriate formula.
Given:
- Percentage by mass of hydrogen peroxide = 24.26%
- Density of the solution = 1.11 g/cm^3
To calculate the molarity (M) of a solution, we need to know the number of moles of solute (in this case, hydrogen peroxide) and the volume of the solution in liters.
Step 1: Calculate the mass of the solution
To find the mass of the solution, we need to know the volume and density.
Density formula: Density = mass/volume
Rearranging the formula to solve for mass: mass = density × volume
Given the density of the solution is 1.11 g/cm^3, we can assume a 1 cm^3 volume of the solution.
mass = 1.11 g/cm^3 × 1 cm^3 = 1.11 g
Step 2: Calculate the mass of hydrogen peroxide
Since the solution is 24.26% hydrogen peroxide by mass, we can multiply the mass of the solution by the mass percentage to find the mass of hydrogen peroxide.
mass of hydrogen peroxide = 24.26% × 1.11 g = 0.269 g
Step 3: Convert the mass of hydrogen peroxide to moles
To convert the mass of hydrogen peroxide to moles, we need to know the molar mass of hydrogen peroxide (H2O2).
Molar mass of H2O2 = (2 × atomic mass of H) + (2 × atomic mass of O)
Atomic mass of H = 1.01 g/mol
Atomic mass of O = 16.00 g/mol
Molar mass of H2O2 = (2 × 1.01 g/mol) + (2 × 16.00 g/mol) = 34.02 g/mol
Now, we can calculate the number of moles:
moles of hydrogen peroxide = mass / molar mass
moles of hydrogen peroxide = 0.269 g / 34.02 g/mol = 0.00791 mol
Step 4: Calculate the volume in liters
To find the volume in liters, we need to convert the volume in cm^3 to liters.
1 cm^3 = 1 × 10^-3 L
volume = 1 cm^3 × 1 × 10^-3 L/cm^3 = 0.001 L
Step 5: Calculate the molarity
Molarity (M) = moles of solute / volume of solution (in liters)
Molarity = 0.00791 mol / 0.001 L = 7.91 M
Therefore, the molarity of the hydrogen peroxide solution is 7.91 M.
Looking at the given answer choices, none of them match the calculated molarity of 7.91 M.