Name 1 Equivalence point of acid when titrated with NaOH is

Name

1. Equivalence point of acid when titrated with NaOH is at a pH greater than 7. Which acid can be eliminated from the list, and why?

2. Using a .500 M NaOH and a pH meter, you got the titration curve below. Which two acids can be eliminated from the list and why (allowing inaccurate measurements owing to the calibration of meter). And what is the molar concentration of original acid solution?

3. Finally you are given 22.2g of your unknown acid in solid form, which is dissolved in 1.00kg of water. You use dry ice and a thermometer to measure the cooling curve for this solution and determine the freezing point to be -.9°C. Which acid is it? and why? Compute van\'t Hoff factor for choosen acid at this concentration to validate argument.

I already look into many websites and youtube videos, I also went back to my Laboratory notes and I can\'t find any way of solving this. And I can\'t remember how to solve it.

Name	Formula	Ka
Acetic acid	CH3COOH	1.76E-5
Formic Acid	HCOOH	1.77E-4
Hydrazoic Acid	HN3	1.90E-5
Lactic Acid	CH3CH(OH)COOH	1.38-4
Nitric Acid	HNO3	>>1

Titration Curve of Unknown Acid pH 14 r 12 10 4 2 VNaOH Added 50 10 20 30 40 0

Solution

1.

Since at equivalence point pH> 7

This means it is a weak acid

So we can surely eliminate HNO3 from the list as it s a strong acid and others are weak acid

2.

equivalence point for this reactipon is at pH = 8

So we can eliminate HNO3 for sure , because equivalence point in this case will be at pH=7

Also this curve has 1 point of equivalence. This means this corrsponds to a mono protic acid.

So we can eliminate Lactic acid , which is a diprotic acid.