SECTION-3 (Maximum Marks: 24)

• This section contains SIX (06) questions. The answer to each question is a NUMBERICAL VLAUE.

• For each question, enter the correct numerical value of the answer using the mouse and the on-screen virtual numeric keypad in the place designated to enter the answer. If the numerical value has more than two decimal places, truncate round-off the value to TWO decimal places.

• Answer to each question will be evaluated according to the following making scheme:

Full Marks : +4 If ONLY the correct numerical value is entered;

Zero Marks : 0 In all other cases.

5.00 mL of 0.10 M oxalic acid solution taken in a conical flask is titrated against NaOH from a burette using phenolphthalein indicator. The volume of NaOH required for the appearance of permanent faint pink color is tabulated below for five experiments. What is the concentration, in molarity, of the NaOH solution?

Exp. No. Vol. of NaOH (mL))

1 12.5

2 10.5

3 9.0

4 9.0

5 9.0