Calculate the normality of a 15% H2SO4 (MW=98g/n) solution. The density of the solution is 1.21 g/mL
15% H2SO4(what? w/w).
15 g H2SO4/100 g soln
15/98 = mols H2SO4
M H2SO4 = mols H2SO4/100 g soln
Use density to convert 100 g soln to volume, convert to L and M = mols/L soln.
Then N = 2*M.
Post your work if you get stuck.
15g H2SO4/ 100g soln x 1.21g soln/1ml soln x 1000ml soln/ 1L soln x 1equiv H2SO4/98g H2SO4 = 1.852N
To calculate the normality of a solution, we need to first understand what it represents. Normality (N) measures the molar concentration of reactive entities in a solution.
To find the normality of a given solution, we need the following information:
1. The molar mass of the solute (in this case, H2SO4).
2. The volume of the solution (in liters) or the weight of the solute (in grams).
3. The stoichiometry of the reaction (to determine the number of moles of reactive entities per mole of solute).
Given information:
- H2SO4 molar mass (MW) = 98 g/mol
- Solution density = 1.21 g/mL (or 1.21 g/cm³)
To calculate the normality, we'll follow these steps:
Step 1: Convert the given percentage concentration of H2SO4 to grams per liter (g/L) or moles per liter (mol/L).
- Since we know the density of the solution is 1.21 g/mL, we can convert this to g/L by multiplying by 1000 mL/L:
Solution density = 1.21 g/mL * 1000 mL/L = 1210 g/L
- 15% H2SO4 means that there are 15 grams of H2SO4 per 100 grams of the solution.
Mass of H2SO4 in the solution = (15 g/100 g) * 1210 g/L = 181.5 g/L
Step 2: Calculate the number of moles of H2SO4 in the solution.
- Moles of solute (H2SO4) = (mass of solute (g) / molar mass of H2SO4)
Moles of H2SO4 = 181.5 g/L / 98 g/mol = 1.85 mol/L
Step 3: Determine the normality by considering the stoichiometry of the reaction.
- H2SO4 is a diprotic acid, which means each mole of H2SO4 can donate two moles of H+ ions.
Normality (N) = Moles of H2SO4 * Number of moles of H+ ions per mole of H2SO4 * 2
Normality = 1.85 mol/L * 2 = 3.70 N
Therefore, the normality of the 15% H2SO4 solution is 3.70 N.