How many milliliters of 0.02 M HCl are needed to react completely with 100 mL of 0.01 M NaOH?

A200 mL
B100 mL
C75 mL
D50 mL
E25 mL

Verified Answer :

The reaction of HCl and NaOH is HCl + NaOH = NaCl + H2O. So the mole number of HCl and NaOH is equal. So the volume of HCl =0.01*0.1/0.02=0.05 L =50 ml. So the answer is D).

Answer: Option (D) is the correct answer.

Explanation:

Molarity is number of moles divided by volume of the solution.

Mathematically,     Molarity = \(\frac{no. of moles}{Volume}\)

Also, in the given situation number of moles of both HCl and NaOH are equal. Therefore, volume of HCl will be calculated as follows.

               \(M_{HCl}V_{HCl}\) = \(M_{NaOH}V_{NaOH}\)

               \(0.02 M \times V_{HCl}\) = \(0.01 M \times 100 mL\)

                \(V_{HCl}\) = \(\frac{0.01 M \times 100mL}{0.02}\)

                                              = 50 mL

Thus, we can conclude that volume of HCl is 50 mL.