A 10.0% by mass H2SO4(aq) solution has a density of 1.07 g/mL.
(a) How many milliliters of solution contain 8.41 g of H2SO4?
(b) What is the molality of H2SO4 in solution?
(c) What mass (in grams) of H2SO4 is in 258 mL of solution?
To solve these problems, we need to use the formula for mass percent and understand how to convert between different units.
(a) The mass percent formula is:
Mass percent = (mass of solute / mass of solution) * 100%
Given:
Mass percent = 10.0% = 10.0 g/100 mL
Density = 1.07 g/mL
Mass of solution = Volume of solution * Density
To find the volume of the solution containing 8.41 g of H2SO4, we can use the following steps:
Step 1: Calculate the mass of the solution.
Mass of solution = Volume of solution * Density
Since we are given the density as 1.07 g/mL, we can rearrange the formula to find the mass of the solution:
Mass of solution = Volume of solution * 1.07 g/mL
Step 2: Calculate the volume of the solution.
Using the mass percent formula, we can express the mass of the solute in terms of the mass of the solution:
Mass of solute = (mass percent / 100) * mass of solution
Rearranging the formula, we can solve for the volume of the solution:
Volume of solution = Mass of solute / Density
Now we can substitute the given values to find the volume of the solution containing 8.41 g of H2SO4:
Volume of solution = 8.41 g / 1.07 g/mL
(b) To find the molality (m) of H2SO4 in the solution, we need to calculate the number of moles of H2SO4 and then divide it by the mass of the solvent (in kilograms).
Step 1: Calculate the number of moles of H2SO4.
Number of moles = Mass of H2SO4 / Molar mass of H2SO4
The molar mass of H2SO4 can be found by adding up the atomic masses of its elements:
Molar mass of H2SO4 = (2 * atomic mass of hydrogen) + (1 * atomic mass of sulfur) + (4 * atomic mass of oxygen)
Step 2: Calculate the mass of the solvent.
Mass of solvent = Mass of solution - Mass of solute
Step 3: Convert the mass of the solvent to kilograms.
Mass of solvent (in kg) = Mass of solvent / 1000
Step 4: Calculate the molality of H2SO4.
Molality (m) = Number of moles of H2SO4 / Mass of solvent (in kg)
(c) To find the mass of H2SO4 in 258 mL of the solution, we can use a similar approach to part (a).
Step 1: Calculate the mass of the solution using the density.
Mass of solution = Volume of solution * Density
Step 2: Calculate the mass of H2SO4 using the mass percent formula.
Mass of H2SO4 = (mass percent / 100) * mass of solution
Now, let's plug in the values and calculate the answers.