Final answer:
To titrate 34.00 mL of 0.140 M HBr to the equivalence point, 23.8 mL of 0.200 M NaOH is needed. The calculation is based on the molar ratio of the reaction between HBr and NaOH, which is 1:1.
Step-by-step explanation:
To calculate the volume of 0.200 M NaOH needed to titrate 34.00 mL of 0.140 M HBr to the equivalence point, we can use the concept of molarity and stoichiometry in a titration. In a titration of a strong acid with a strong base, the chemical reaction is:
HBr(aq) + NaOH(aq) → NaBr(aq) + H₂O(l)
This reaction has a 1:1 molar ratio between HBr and NaOH. First, calculate the moles of HBr present:
Moles of HBr = Molarity of HBr × Volume of HBr (in liters)
= 0.140 M × 0.034 L = 0.00476 mol
Since the molar ratio of HBr to NaOH is 1:1, the moles of NaOH needed will also be 0.00476 mol. We can then find the volume of NaOH needed by rearranging the molarity equation:
Volume of NaOH = Moles of NaOH / Molarity of NaOH
= 0.00476 mol / 0.200 M = 0.0238 L
Converting liters to milliliters, we get:
Volume of NaOH = 0.0238 L × 1000 mL/L = 23.8 mL
Therefore, we would need 23.8 mL of 0.200 M NaOH to reach the equivalence point in the titration with 34.00 mL of 0.140 M HBr.