A 27.00mL sample of an H2SO4 solution of unknown concentration is titrated with a 0.1422M KOH solution. A volume of 40.22mL of KOH was required to reach the equivalence point.
What is the concentration of the unknown H2SO4 solution?
Any help would be greatly appreciated. (:
H2SO4 + 2KOH ==> K2SO4 + 2H2O
mols KOH = M x L = ?
Convert mols KOH to mols H2SO4 using the coefficients in the balanced equation.
Then M H2SO4 = mols H2SO4/L H2SO4
To find the concentration of the unknown H2SO4 solution, we can use the concept of stoichiometry and the balanced chemical equation for the reaction between H2SO4 and KOH.
The balanced chemical equation is:
H2SO4 + 2KOH → K2SO4 + 2H2O
From the balanced equation, we can see that it takes 2 moles of KOH to react with 1 mole of H2SO4.
First, let's calculate the number of moles of KOH used in the titration:
moles of KOH = molarity of KOH × volume of KOH used (in L)
moles of KOH = 0.1422 M × 0.04022 L = 0.005731 moles
Since the stoichiometry of the balanced equation is 2:1 (2 moles of KOH needed for 1 mole of H2SO4), the number of moles of H2SO4 present in the solution is half the number of moles of KOH used:
moles of H2SO4 = 0.005731 moles ÷ 2 = 0.0028655 moles
Now, let's calculate the concentration of the H2SO4 solution:
concentration of H2SO4 = moles of H2SO4 ÷ volume of H2SO4 (in L)
volume of H2SO4 = 27.00 mL = 0.02700 L
concentration of H2SO4 = 0.0028655 moles ÷ 0.02700 L ≈ 0.1061 M
Therefore, the concentration of the unknown H2SO4 solution is approximately 0.1061 M.
To find the concentration of the unknown H2SO4 solution, we can use the concept of stoichiometry.
First, we need to determine the moles of KOH used in the titration. We can calculate this by multiplying the volume of KOH used (40.22 mL) by the concentration of KOH (0.1422 M):
Moles of KOH = Volume of KOH (in liters) x Concentration of KOH
= 40.22 mL x (1 L / 1000 mL) x 0.1422 M
= 0.00573 mol
Next, we need to determine the moles of H2SO4 in the balanced chemical equation that corresponds to the reaction between KOH and H2SO4. From the balanced equation:
H2SO4 + 2KOH -> K2SO4 + 2H2O
We can see that the stoichiometric ratio between H2SO4 and KOH is 1:2. This means that for every 1 mole of H2SO4, we need 2 moles of KOH to react completely.
Therefore, the moles of H2SO4 in the titration can be calculated by multiplying the moles of KOH by 1/2:
Moles of H2SO4 = Moles of KOH x (1 mole H2SO4 / 2 moles KOH)
= 0.00573 mol x (1 mol / 2 mol)
= 0.00287 mol
Finally, we need to calculate the concentration of the H2SO4 solution. The concentration is defined as moles of solute divided by the volume of the solution in liters:
Concentration of H2SO4 = Moles of H2SO4 / Volume of solution (in liters)
= 0.00287 mol / (27.00 mL x (1 L / 1000 mL))
= 0.1063 M
So, the concentration of the unknown H2SO4 solution is 0.1063 M.