If a chemist titrates 300.0 mL of H2SO4 with a 3.0 M solution of NaOH and requires only 3.4 mL of the base to reach the endpoint, what is the concentration of the sulfuric acid?
To find the concentration of the sulfuric acid (H2SO4), we can use the concept of stoichiometry and the balanced equation for the reaction between sulfuric acid and sodium hydroxide (NaOH).
The balanced equation for the reaction is:
H2SO4 + 2NaOH -> Na2SO4 + 2H2O
We can see from the equation that one molecule of sulfuric acid reacts with 2 molecules of sodium hydroxide. Therefore, the molar ratio is 1:2.
To calculate the concentration of the sulfuric acid, we need to determine the number of moles of NaOH used in the titration.
Given:
Volume of NaOH used = 3.4 mL
Molarity of NaOH = 3.0 M
First, convert the volume of NaOH used from milliliters to liters:
3.4 mL = 3.4/1000 = 0.0034 L
Next, calculate the number of moles of NaOH used:
Moles of NaOH = Molarity × Volume (in liters)
Moles of NaOH = 3.0 M × 0.0034 L = 0.0102 mol
Since the molar ratio between H2SO4 and NaOH is 1:2, the number of moles of H2SO4 is half the moles of NaOH used:
Moles of H2SO4 = 0.0102 mol / 2 = 0.0051 mol
Finally, to find the concentration of H2SO4, divide the moles of H2SO4 by the volume of H2SO4 used in the titration:
Volume of H2SO4 used = 300.0 mL = 0.3 L
Concentration of H2SO4 = Moles of H2SO4 / Volume of H2SO4
Concentration of H2SO4 = 0.0051 mol / 0.3 L = 0.017 M
Therefore, the concentration of the sulfuric acid is 0.017 M.
2NaOH + H2SO4 ==> Na2SO4 + 2H2O
moles NaOH = M x L = ?
Look at the equation. moles H2SO4 = 1/2 * moles NaOH.
Then MH2SO4 = moles H2SO4/L H2SO4.
Solve for M H2SO4.