How many grams of hydrogen peroxide (H2O2) must be added to 1,500 mL of water to produce a concentration of 1.33 m (molal solution)?
To calculate the amount of hydrogen peroxide (H2O2) needed to produce a 1.33 m (molal) solution, you'll need to use the formula:
molality (m) = moles of solute / mass of solvent (kg)
Since we want to find the mass of hydrogen peroxide (H2O2) needed and the volume of water given is in milliliters, we need to convert it to kilograms:
Mass of water (kg) = Volume of water (mL) / 1000
Mass of water (kg) = 1500 mL / 1000 = 1.5 kg
Next, we need to calculate the number of moles of hydrogen peroxide (H2O2) required:
molality (m) = moles of H2O2 / 1.5 kg
The molality is given as 1.33 m, so we can rearrange the formula to find the moles of H2O2:
moles of H2O2 = 1.33 m * 1.5 kg
moles of H2O2 = 1.995
Since the molar mass of hydrogen peroxide (H2O2) is approximately 34 g/mol, we can calculate the mass of H2O2 needed using the following formula:
mass of H2O2 (g) = moles of H2O2 * molar mass of H2O2
mass of H2O2 (g) = 1.995 mol * 34 g/mol
mass of H2O2 (g) = 67.83 g
Therefore, approximately 67.83 grams of hydrogen peroxide (H2O2) must be added to 1,500 mL of water to produce a concentration of 1.33 m (molal solution).
To find the number of grams of hydrogen peroxide (H2O2) needed to produce a 1.33 m solution in 1,500 mL of water, we need to use the formula for molality:
Molality (m) = moles of solute / mass of solvent (in kg)
First, we need to convert the volume of water from milliliters (mL) to kilograms (kg):
Mass of water (in kg) = volume of water (in mL) * density of water
The density of water is approximately 1 g/mL, so:
Mass of water (in kg) = 1,500 mL * 1 g/mL / 1,000 = 1.5 kg
Now, we can rearrange the molality formula to solve for the moles of solute:
moles of solute = Molality (m) * mass of solvent (in kg)
Given that the molality (m) is 1.33 m and the mass of the water (solvent) is 1.5 kg, we can calculate the moles of solute:
moles of solute = 1.33 mol/kg * 1.5 kg = 1.995 moles
Since hydrogen peroxide (H2O2) has a molar mass of approximately 34 g/mol, we can convert moles to grams:
grams of H2O2 = moles of solute * molar mass of H2O2
grams of H2O2 = 1.995 moles * 34 g/mol = 67.83 grams
Therefore, you would need to add approximately 67.83 grams of hydrogen peroxide (H2O2) to 1,500 mL of water to produce a concentration of 1.33 m (molal solution).