Hey there! Sign in to join this conversationNew here? Join for free
    • Thread Starter
    Offline

    0
    ReputationRep:
    It goes as follows:

    >Knowing Ks = 6*10^-38 for Fe(OH)3 in neutral solutions, calculate the minimum hydronium ion concentration of an acidic solution in order to completely dissolve 10 mg of Fe(OH)3. Data: Volume = 0.1 L.

    Edit:
    My idea was to calculate the amount of iron and hydroxide ions, and then add enough acid containing hydronium ions in order to neutralise the hydroxide. To do this I used the equilibrium constant leaving the hydroxide ions as the unknown. Then I calculated the difference between the initial hydroxide concentration (corresponding to 10 mg of salt) and the needed concentration to reach Ks. This corresponds to the concentration of hydronium ions in the acidic solution, and I can calculate pH.

    Doing this I get pH= 3.03. Is this how it should be done?
 
 
 
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • Poll
    What newspaper do you read/prefer?
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • 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

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