Turn on thread page Beta
    • Thread Starter
    Offline

    13
    ReputationRep:
    Name:  image-76ddb5e8-b53d-4e29-961d-bddd18ad3634848429261-compressed.jpg.jpeg
Views: 9
Size:  23.0 KB

    can someone please explain how to work this out (the answer is B)

    thanks xx
    Posted on the TSR App. Download from Apple or Google Play
    Offline

    11
    ReputationRep:
    pH is defined as -log[H+].

    You know the initial concentration of [H+] since the acid is strong and monoprotic (one proton given out by each acid molecule).
    pHinitial = -log(1) = 0

    No matter how much water you add, the amount of H+ doesn't vary
    ninitial = nfinal therefore (cinitial)(Vinitial) = (cfinal)(Vfinal)
    cfinal = 0.01 mol dm-3 therefore pHfinal = 2

    ΔpH = 2
    • Thread Starter
    Offline

    13
    ReputationRep:
    (Original post by zoae)
    pH is defined as -log[H+].

    You know the initial concentration of [H+] since the acid is strong and monoprotic (one proton given out by each acid molecule).
    pHinitial = -log(1) = 0

    No matter how much water you add, the amount of H+ doesn't vary
    ninitial = nfinal therefore (cinitial)(Vinitial) = (cfinal)(Vfinal)
    cfinal = 0.01 mol dm-3 therefore pHfinal = 2

    ΔpH = 2
    I see, thank you!!
 
 
 
Reply
Submit reply
Turn on thread page Beta
Updated: March 1, 2018
Poll
Do you think parents should charge rent?

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.