Question

What volume (in mL) of 0.200 M NaOH do we need to titrate 36.00 mL of 0.140 M HBr to the equivalence point?

A) 18.00 mL
B) 36.00 mL
C) 54.00 mL
D) 72.00 mL

Answer 1

To find the volume of 0.200 M NaOH required to titrate 36.00 mL of 0.140 M HBr, one must calculate the moles of HBr, use the 1:1 molar ratio in the reaction with NaOH, and then calculate the needed NaOH volume, resulting in 25.20 mL.

Step-by-step explanation:

To determine the volume (in mL) of 0.200 M NaOH needed to titrate 36.00 mL of 0.140 M HBr to the equivalence point, we can apply the concept of stoichiometry.

In a titration involving a strong acid and a strong base, they react in a 1:1 mole ratio. We first calculate the moles of HBr in the solution using its concentration and volume.

Moles of HBr = 0.140 M × 0.036 L = 0.00504 mol

Because of the 1:1 mole ratio, moles of NaOH required will be the same:

Moles of NaOH = 0.00504 mol

Then, we can find the volume of NaOH needed by rearranging the concentration formula (M = moles/L):

Volume of NaOH = Moles of NaOH / Molarity of NaOH = 0.00504 mol / 0.200 M = 0.0252 L

Converting liters to milliliters (1 L = 1000 mL), we get:

Volume of NaOH = 0.0252 L × 1000 mL/L = 25.20 mL

Thus, the correct answer is not listed among the provided options A) 18.00 mL, B) 36.00 mL, C) 54.00 mL, or D) 72.00 mL.