Question

hydrogen peroxide is a powerful oxidizing agent; it is used in concentrated solution in rocket fuel and in dilute solution in hair bleach. an aqueous solution is 33% by mass and has a density of 1.28 g/ml. calculate the mole fraction of H₂O₂. enter to 2 decimal place.

Answer 1

The mole fraction of hydrogen peroxide in a 33% solution by mass with a density of 1.28 g/ml is 0.21.

Step-by-step explanation:

To calculate the mole fraction of hydrogen peroxide (H2O2) in a 33% solution by mass with a density of 1.28 g/ml, we'll follow these steps:

• Determine the mass of 1 ml of the solution: 1 ml × 1.28 g/ml = 1.28 g
• Calculate the mass of H2O2 in that 1 ml: 33% of 1.28 g = 0.4224 g
• Convert the mass of H2O2 to moles: 0.4224 g × (1 mole/34.02 g) = 0.01242 moles
• Calculate the mass of water in 1 ml of the solution: (1 - 0.33) × 1.28 g = 0.8576 g
• Convert the mass of water to moles: 0.8576 g × (1 mole/18.02 g) = 0.04759 moles
• Add the moles of H2O2 and water to get the total moles in the solution: 0.01242 moles + 0.04759 moles = 0.06001 moles
• Finally, calculate the mole fraction of H2O2: 0.01242 moles / 0.06001 moles = 0.207−5, or to two decimal places, 0.21.