阿King asked in 科學化學 · 1 decade ago

急問 化學題目 關於溶液

Crtric acid , which can be obtained from lemon juice , has the molecular

formula C6H8O7. A 0.250-g sample of citric acid dissolved in 25.0mL

of water requires 37.2 mL of 0.105 M NaOH for complete neutralization.

What number of acidic hydrogens per molecule does citric acid have?

Answer : Citric acid has three acidic hydrogens per citric acid molecule

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  • Anonymous
    1 decade ago
    Favorite Answer

    First of all, molar mass of citric acid is:

    6 × 12 + 8 × 1 + 7 × 16 = 192 g/mol

    Then, no. of moles of citric acid used = 0.25/192 = 0.00130

    Also, no. of moles of NaOH used = 0.105 × 37.2/1000 = 0.00390

    Hence, mole ratio of citric : NaOH = 1 : 3

    Therefore, number of acidic hydrogns per molecule that citric acid has is 3.

    Source(s): My chemical knowledge
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