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    Hey, I really need urgent help with this chemistry problem.

    How would I dilute 0.005M iodine solution to 0.004, then from 0.004 to 0.003 etc.? What factor do I dilute it by? It's probably straightforward but I dont know how to do it. I can't ask my chem teacher because I'm on my holidays...

    Thank you so much!
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    Say if you had 5 ml of 0.005M you can take 4 ml of this solution and add 1 ml of water to it to get 5ml of 0.004M. Make sense?
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    (Original post by EierVonSatan)
    Say if you had 5 ml of 0.005M you can take 4 ml of this solution and add 1 ml of water to it to get 5ml of 0.004M. Make sense?
    Ah, I see, I see...lol that sounds simple

    So then to make 0.003 from 0.004 you just take 3 ml of this solution and add 1 ml of water to it? And then you keep doing that? I feel I'm missing something major here...

    Does m1v1 = m2v2 come into this? So say if I had 25cm3 of 0.004M then to get 0.003M I would need 33.3 cm3 of water?
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    (Original post by Gooner786)
    Ah, I see, I see...lol that sounds simple
    I made the volumes simple

    So then to make 0.003 from 0.004 you just take 3 ml of this solution and add 1 ml of water to it? And then you keep doing that? I feel I'm missing something major here...
    Nope, that's not right.

    Does m1v1 = m2v2 come into this? So say if I had 25cm3 of 0.004M then to get 0.003M I would need 33.3 cm3 of water?
    I don't ever recall using that equation...you mean concentration = moles/volume?

    All you have to do is keep perspective on the number of moles you have :yes:

    So 25cm3 of 0.004 M = 0.0001 moles

    concentration you want = 0.003 M so the volume you need is indeed 33.3 cm3
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    (Original post by EierVonSatan)
    I made the volumes simple



    Nope, that's not right.



    I don't ever recall using that equation...you mean concentration = moles/volume?

    All you have to do is keep perspective on the number of moles you have :yes:

    So 25cm3 of 0.004 M = 0.0001 moles

    concentration you want = 0.003 M so the volume you need is indeed 33.3 cm3
    Ahh I see...

    One last thing (sorry for the questions lol), but 33.3 cm3 is the volume of 0.003M solution I need. What I'm wondering is how much water I need to add to the 25cm3 of 0.004M solution to obtain 0.003M...so would that just be 33.3-25 = 8.3cm3 of water?

    Thanks so far by the way, youve been a great help

    EDIT: I might be overcomplicating things...
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    (Original post by Gooner786)
    Ahh I see...

    One last thing (sorry for the questions lol), but 33.3 cm3 is the volume of 0.003M solution I need. What I'm wondering is how much water I need to add to the 25cm3 of 0.004M solution to obtain 0.003M...so would that just be 33.3-25 = 8.3cm3 of water?

    Thanks so far by the way, youve been a great help

    EDIT: I might be overcomplicating things...
    Yep, just the simple subtraction will get you the amount of water you need to add
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    (Original post by EierVonSatan)
    Yep, just the simple subtraction will get you the amount of water you need to add
    Awesome! Thanks for all the help!
 
 
 
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