• Want to take part in this year's BoS Trials event for Maths and/or Business Studies?
    Click here for details and register now!
  • YOU can help the next generation of students in the community!
    Share your trial papers and notes on our Notes & Resources page

Titrating a strong acid and strong base using phenolphtalein (1 Viewer)

cutemouse

Account Closed
Joined
Apr 23, 2007
Messages
2,250
Gender
Undisclosed
HSC
N/A
Hi,

I understand that the range for Phenolphthalein is pH 8.3 - 10

But when titrating a strong acid and base (eg NaOH and H2SO4) the product will be pH 7... so I don't understand why you can use phenolphthalein for this. Could someone please explain it for me?

Thanks
 

shady145

Banned
Joined
Dec 4, 2008
Messages
1,687
Gender
Female
HSC
2014
have u seen a graph for this type of reaction
ph against NaOH (mL) graph
it shows 1 drop of base at the equivalence pt makes ph go from 3 to 10, since phenolpthaleins ph indicator is in the region it is acceptable to use it for a strong acid strong base titration.
 

cutemouse

Account Closed
Joined
Apr 23, 2007
Messages
2,250
Gender
Undisclosed
HSC
N/A
Yeah... But if it's pH 7, then phenolphthalein will still be clear and show no colour changes... so...?
 

shady145

Banned
Joined
Dec 4, 2008
Messages
1,687
Gender
Female
HSC
2014
do u have jacarnada? it has it in there i think. the graph. if u dnt i can send u an electronic copy of it i have on my laptop
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top