An unknown acid was titrated two times with 0.10 M NaOH. The first titration was done using an indicator to determine the equivalence point volume. A second titration was carried out where the pH was determined throughout the entire titration. The data is given below. Titration 1: mL unknown acid = 25.0, mL of NaOH needed to reach equivalence point = 30.00
Titration 2: mL unknown acid = 25.0
mL 0.1M pH
NaOH Added
0.0 3.72
5.0 5.82
10.0 6.22
15.0 6.52
20.0 6.82
25.0 7.22
30.0 9.63
35.0 11.92
a. What is the concentration of the unknown acid?
b. What is the Ka of the unknown acid?
c. Which of the indicators given below would be a good choice to use in the titration of this acid with the NaOH?

hello your question is incomplete attached below is the complete question

a) 0.12 M

b) Ka = 3.0 * 10^-7

c) Alizarin Yellow R

Explanation:

A) Determine the concentration of the unknown acid

The PH of the unknown acid before addition of NaOH is ; 3.72 ( weak acid )

First determine the moles of of NaOH

= molarity * volume

= 0.10 M * 30.0 ML = 0.0030 mol

at equivalence point

moles of NaOH = moles of unknown acid = 0.0030 mol

volume of unknown acid = 25.0 mL

Next calculate the concentration of the Acid ( HA )

= moles / volume

= 0.0030 mol / 25.0 mL

= 0.12 M

b) Determine the Ka of the unknown acid

attached below is the detailed solution

Ka = 3.0 * 10^-7

c) The indicator that would be a good choice to use in the titration of this acid with NaOH is ; Alizarin Yellow R . this is because the titration is between a strong base and a weak acid.

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.