Question

Can Someone Please Help Me Solve These TWO Questions? (:

Determine the volume of sodium hydroxide added to the flask from the buret.

Calculate the molarity of the hydrochloric acid in the flask.

Answer 1

I don't think there is enough information provided to answer these questions.

Answer 2

How would I go about answering these questions?

Answer 3

Are there any numbers involved in the problem? You have nothing to calculate as it is!

Answer 4

it was a lab i did and i have to answer these questions based off the data I collected....

Measurement
Volume of HCl used
20.0 mL
Initial volume of NaOH in buret
50.0 mL
Final volume of NaOH in buret
34.0 mL



What was Measured
Measurement
Volume of HCl used
30.0 mL
Initial volume of NaOH in buret
50.0 mL
Final volume of NaOH in buret when end point was reached
26.0 mL
Initial pH of HCl
0.70
pH after 5 mL NaOH added
0.87
pH after 10 mL (total) NaOH added
1.06
pH after 15 mL NaOH added
1.30
pH after 20 mL NaOH added
1.70
Volume at which pH=7.0
24.0 mL NaOH added to the flask (26.0 mL left in buret)
pH after 25 mL NaOH added
11.65
pH after 30 mL NaOH added
12.40
pH after 35 mL NaOH added
12.63
pH after 40 mL NaOH added
12.76
pH after 45 mL NaOH added
12.85
pH after 50 mL NaOH added
12.91

Answer 5

Thats all the info I have (:

Answer 6

Much better. It looks like you already answered the first question within that text: 24.0 ml of NaOH have been added to the flask from the buret.

Answer 7

Thanks!! How do I answer #2?

Answer 8

We need one more value - do you know the concentration of the NaOH that you used in the buret?

Answer 9

No I don't :(

Answer 10

Double, triple check - maybe it is in the instructions? You can't answer the question without it.

Answer 11

Wait - according to your data you measured the pH of the HCl alone, before you added NaOH. Is this true?

Answer 12

yes

Answer 13

OK, then you know that pH = -log([H+])

so 0.70 = -log([H+])

[H+] = 10^(-0.70)

[H+] = 0.199526 ~ 0.200 M

the same goes for [HCl] since for every H+ ion you have a molecule of HCl.

Sorry for the false alarm earlier.

Answer 14

So my answer would be 0.200 M ?

Answer 15

Yes, I think so.

Answer 16

Okay thanks your a life savor!! (: