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    Hey guys! I have been stuck with these type of questions recently.. Could you please help me understand how to do number 2) c)? Thanks a lot!!
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    (Original post by Sandy_Vega30)
    Hey guys! I have been stuck with these type of questions recently.. Could you please help me understand how to do number 2) c)? Thanks a lot!!
    A standard electrode potential is measured when you start with exactly 1 mole of chromium 3 in the solution. In chromium 3 sulphate, each molecule contains 2 chromium atoms, thus, each mole of chromium 3 sulphate molecules contains 2 moles of chromium atoms, but you only want 1 mole of chromium atoms, then how many moles of chromium 3 sulphate do you need? Well, half a mole. If the mass of a mole of chromium 3 sulphate is 300g or whatever, then how grams are there in half a mole of chromium 3 sulphate?
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    (Original post by oShahpo)
    A standard electrode potential is measured when you start with exactly 1 mole of chromium 3 in the solution. In chromium 3 sulphate, each molecule contains 2 chromium atoms, thus, each mole of chromium 3 sulphate molecules contains 2 moles of chromium atoms, but you only want 1 mole of chromium atoms, then how many moles of chromium 3 sulphate do you need? Well, half a mole. If the mass of a mole of chromium 3 sulphate is 300g or whatever, then how grams are there in half a mole of chromium 3 sulphate?
    Thanks a lot! But do we want only one mole of Chromium ions? What's the reason for that?
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    (Original post by Sandy_Vega30)
    Thanks a lot! But do we want only one mole of Chromium ions? What's the reason for that?
    Yea we do. The electrode potential of a cell varies with the concentration. The higher the concentration, the more they push (or pull) against the electrode and thus the electrode potential varies. Hence, chemists need to agree on a standard concentration to measure the potential difference with, it just so happens that 1 mol is the concentration they chose to be the standard.
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    (Original post by oShahpo)
    Yea we do. The electrode potential of a cell varies with the concentration. The higher the concentration, the more they push (or pull) against the electrode and thus the electrode potential varies. Hence, chemists need to agree on a standard concentration to measure the potential difference with, it just so happens that 1 mol is the concentration they chose to be the standard.
    Thanks a lot!! You are a life saver!!
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    (Original post by Sandy_Vega30)
    Thanks a lot!! You are a life saver!!
    Let me know if you have any more questions ^_^
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    (Original post by oShahpo)
    Let me know if you have any more questions ^_^
    Sure!
 
 
 
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