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    How many moles of ions are present in 30 cm3 of 0.025 mol dm-3 barium hydroxide solution, Ba(OH)2(aq)?

    A) 0.00075

    B) 0.00150

    C) 0.00225

    D) 0.00450


    What i did is that i found out moles first then multiplied by Avagadro Constant which gives answer A. But its wrong. The answer is C.

    Can anyone explain me in a detailed manner please? Thank you for your time
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    So you have calculated the moles first which is correct. How many ions are formed in a solution of barium hydroxide?
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    You don't need to multiply by Avagadro's constant as the question is asking about moles not molecules.

    The number of moles of Ba(OH)2 is the same as A, but you're looking for the number of ions. How many ions are there in Ba(OH)2?
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    (Original post by JAR123)
    So you have calculated the moles first which is correct. How many ions are formed in a solution of barium hydroxide?
    3? 2 of OH and 1 of Ba
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    (Original post by EierVonSatan)
    You don't need to multiply by Avagadro's constant as the question is asking about moles not molecules.

    The number of moles of Ba(OH)2 is the same as A, but you're looking for the number of ions. How many ions are there in Ba(OH)2?
    3? 2 of OH and 1 of Ba
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    What year are you in?
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    (Original post by dajjal619)
    3? 2 of OH and 1 of Ba
    Exactly so multiply your mol value by 3
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    (Original post by dajjal619)
    How many moles of ions are present in 30 cm3 of 0.025 mol dm-3 barium hydroxide solution, Ba(OH)2(aq)?

    A) 0.00075

    B) 0.00150

    C) 0.00225

    D) 0.00450


    What i did is that i found out moles first then multiplied by Avagadro Constant which gives answer A. But its wrong. The answer is C.

    Can anyone explain me in a detailed manner please? Thank you for your time
    Moles = Concentration x Volume
    Moles = 0.03 x 0.025 = 0.00075
    Moles Ba ions = 0.00075
    Moles OH ions = 0.00075 x 2= 0.0015
    Total moles of ions = 0.00225
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    (Original post by EierVonSatan)
    Exactly so multiply your mol value by 3
    Thanks Sir! got it
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    (Original post by Agrey)
    Moles = Concentration x Volume
    Moles = 0.03 x 0.025 = 0.00075
    Moles Ba ions = 0.00075
    Moles OH ions = 0.00075 x 2= 0.0015
    Total moles of ions = 0.00225

    Yes Got It. Thanks
 
 
 
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