A solution contains Al3 and Co2 . The addition of 0.3868 L of 1.707 M NaOH results in the complete precipitation of the ions as Al(OH)3 an

Question

A solution contains Al3 and Co2 . The addition of 0.3868 L of 1.707 M NaOH results in the complete precipitation of the ions as Al(OH)3 and Co(OH)2 . The total mass of the precipitate is 23.36 g . Find the masses of Al3 and Co2 in the solution.

in progress 0
Thu Cúc 2 days 2021-07-19T20:47:28+00:00 1 Answers 1 views 0

Answers ( )

    0
    2021-07-19T20:48:31+00:00

    Answer:

    See Explanation

    Explanation:

    Number of moles of NaOH = 0.3868 L × 1.707 M = 0.660 moles

    Reaction of Al^3+ and OH^-

    Al^3+(aq) + 3OH^-(aq) —–> Al(OH)3(s)

    If 1 mole of Al3+ reacts with 3 moles of OH^-

    x moles of Al^3+ reacts with 0.660 moles of OH^-

    x = 1 × 0.660/3

    x= 0.22 moles

    Mass of Al^3+ = 0.22 moles × 27 g/mol = 5.94 g of Al^3+

    Co^2+(aq) + 2OH^-(aq) —-> Co(OH)2(s)

    1 mole of Co^+ reacts with 2 moles of OH^-

    x moles of Co^2+ reacts with 0.660 moles of OH^-

    x = 1 × 0.660/2 = 0.33 moles

    Mass of Co^2+ = 0.33 moles × 59 g/mol = 19.47 g

Leave an answer

Browse

Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )