Final answer:
To find the concentration of a strong acid using titration data, calculate the moles of the titrant (NaOH) used at the equivalence point and apply these moles to the volume of the acid to find its molarity.
Step-by-step explanation:
When 13.4 mL of 0.25 M NaOH is needed to reach the equivalence point in a titration with 10 mL of a strong acid, the concentration of the acid can be determined using the mole concept. At equivalence, the moles of acid are equal to the moles of base since they react in a 1:1 molar ratio.
We calculate the moles of NaOH by multiplying the volume by its concentration (0.0134 L × 0.25 mol/L = 0.00335 mol). Since the moles are equal at the equivalence point, the acid too has 0.00335 mol. Therefore, the concentration of the acid (C) is calculated using the formula:
C = moles/volume
C = 0.00335 mol / 0.010 L = 0.335 M.
So, the concentration of the strong acid is 0.335 M.