Ph question (1 Viewer)

[Interdice]

56 mL of 0.089 mol L-1 sulfuric acid solution was added to 250 mL of 0.15 mol L-1 sodium hydroxide solution. The volume of the resulting solution was then made up to 500 mL by the addition

I found the chemical equation. I found the concentration of the products which are
[Na2SO4] = 9.97 x 10 ^ -3
[H20] = 1.994 x 10^-4
[H2SO4] = 0 (limiting reagent)
[NaOH] = 1.76 x 10 ^-2

I'm unable to find the PH with these values.

 

[Interdice]

https://thsconline.github.io/s/v/1828/Strathfield%20Girls%202020%20w.%20sol

 

[SadCeliac]

56 mL of 0.089 mol L-1 sulfuric acid solution was added to 250 mL of 0.15 mol L-1 sodium hydroxide solution. The volume of the resulting solution was then made up to 500 mL by the addition

I found the chemical equation. I found the concentration of the products which are
[Na2SO4] = 9.97 x 10 ^ -3
[H20] = 1.994 x 10^-4
[H2SO4] = 0 (limiting reagent)
[NaOH] = 1.76 x 10 ^-2

I'm unable to find the PH with these values.

Find moles of acid and base and then subtract the LR from XS, then convert to conc using your 500mL total volume - then do -log[H+]??? I haven't tried the question but I'm pretty sure that's how you do it

 

[Interdice]

I keep getting 12.138 for some reason

 

[SadCeliac]

I keep getting 12.138 for some reason

I can try and send working - does the paper show solutions?

 

[Interdice]

I can try and send working - does the paper show solutions?

No that's why I asked. Thanks.

 

[SadCeliac]

No that's why I asked. Thanks.

Ahhhh okay - I'll give it a go

 

[SadCeliac]

56 mL of 0.089 mol L-1 sulfuric acid solution was added to 250 mL of 0.15 mol L-1 sodium hydroxide solution. The volume of the resulting solution was then made up to 500 mL by the addition

I found the chemical equation. I found the concentration of the products which are
[Na2SO4] = 9.97 x 10 ^ -3
[H20] = 1.994 x 10^-4
[H2SO4] = 0 (limiting reagent)
[NaOH] = 1.76 x 10 ^-2

I'm unable to find the PH with these values.

Attached is what I got - pH = 12.74


Although I'm not too confident about the n(OH-) in XS, idk if I was meant to multiply n(H2SO4) by 2 because of the molar ratio

Can someone fact check me??

 

[SadCeliac]

https://thsconline.github.io/s/v/1828/Strathfield%20Girls%202020%20w.%20sol

What was the actual answer?

 

[carrotsss]

I keep getting 12.138 for some reason

I could be completely wrong but I just quickly put it in my calculator and got 12.74

 

[SadCeliac]

I could be completely wrong but I just quickly put it in my calculator and got 12.74

THATS WHAT I GOT

 

[carrotsss]

Attached is what I got - pH = 12.74
View attachment 39134

Although I'm not too confident about the n(OH-) in XS, idk if I was meant to multiply n(H2SO4) by 2 because of the molar ratio

Can someone fact check me??

didn’t see this when I posted mine lmao but yes you are supposed to do that, and since we got the same thing ig it’s right !

 

[SadCeliac]

didn’t see this when I posted mine lmao but yes you are supposed to do that, and since we got the same thing ig it’s right !

whooooooo lets goooo

 

[Interdice]

yeah. You got the correct answer. Thank you

 

[SadCeliac]

yeah. You got the correct answer. Thank you

hooray

hope it helped