00:01
Hello everyone let's look at the question.
00:03
So here a titration is done where hl is titated against namh.
00:12
Okay now here some data are given using that data we have to find out or we have to answer certain questions.
00:21
The data given is the concentration of or the molarity of molarity of hl that is taken.
00:31
So it is equal to 0 .3 molar okay and molarity of nah taken is 0 .3 molar okay so the now so the first question that is asked is so we have to write the balanced the chemical equation for the neutralization reaction between hl and naoh now when hcl reacts with nah which what happens it's l acts as an acid and aoh axis strong base right so hcl give all its proton okay so and it will couple with the n -a -o -h giving nacl and so the h plus and oh h -minus they combine to give water so this is the the balance the chemical equation okay so here between xl and n -o -h okay now the second question is so what what was the ph in the color of the solution on the on the beginning at the beginning of the titration okay now so it's ill and an ao it if we take so this titration is done by using phenotheline as an indicator now at the beginning of the titration where an a which is not added so the the phenophilin gives it doesn't give any color when it is present along with hsail okay so here the color of the solution at the the beginning of the titration is it is colorless so it imparts the color only at the end of the titration, okay, only when noh is added.
02:10
So it gives the pink color only in the basic condition or in the acid condition, okay? so it is colorless at the beginning, okay? now, so if you find, if you want to find out the concentration or sorry, the ph of the solution, that is ph of hcl because any which is not added yet.
02:27
That's why.
02:28
So here the ph, the ph is nothing but if you want to find out the ph.
02:37
So it is equal to minus log of concentration of h plus now if you take h cl how it dissociates hcm completely dissociates as h plus and c l minus now we know the concentration of hl so here the concentration of hcl is 0 .3 molar that means since all of the hc l gets dissociated concentration of h plus will also be 0 .3 molar now if we use that minus log of 0 .3 molar that 0 .3 okay now so this is found to be point 5 2 so here the ph of the solution is equal to how much point 52 okay and so what is the color so it is colorless okay now let us move on to the third question so the third question is what is the ph and the color of the solution at the end of the titration at the end of the titration there will be no more hcl so all the hcl reacts with an animal only after you add extra noaah, extra drop of nraoh, you will get a pink color.
03:49
Phinovthaline gives pink when it is in a basic condition.
03:53
So here the color will be pink and if you want to find out the ph.
03:56
So here we cannot find the ph directly.
04:03
We can find out p .o .h.
04:04
After that we can find a ph.
04:05
Now here at the end of the titration there is only n .ao .h.
04:10
Okay, so that 4.
04:11
So, n .o .h...