Anonymous
Anonymous asked in Science & MathematicsChemistry · 2 months ago

Please help me solve this question!!?

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  • 2 months ago

    Since, molarity of formic acid, HCOOH is 0.800M, 1000 ml solution contains 0.800 mole HCOOH. .: e 20ml  0.800M HCOOH= ((20 x 0.800)/1000) mole = 0.016 mole HCOOH.

    Similarity 30 mll 0.800M NaOH = ((30 x 0.800)/1000) mole = 0.029 mole NaOH

    0.016 mole HCOOH will be neutralized by 0.016 mole NaOH (out of 0.024 mole), and hence (0.024-0.016) = 0.008 mole NaOH will remain in 50ml Solution.

    NaOH + HCOOH---> HCOONa + H2O

    [NaOH] excess =(0.008/50 x 1000)= 0.16 mol/L= 0.16 M

    As NaOH is a strong base

    [OH] = [NaOH] = 0.16M   [ NaOH ---> Na+ + OH- ]

    ;. e pOH = -log[OH-] = -log[0.16] = 0.7959

    Again at 25 degrees , pH + pOH = 14

    ;.   pH = 14- pOH = 14 - 0.7959 = 13.2041 aprox. 13.20

    Hence, pH of solution will be 13.20

    please rate Thank you.

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