A 2.87g sample of ascorbic acid (containing C, H, and O only) produces 4.31g CO2 and 1.17g H2O upon combustion. What is the empirical formul

Question

A 2.87g sample of ascorbic acid (containing C, H, and O only) produces 4.31g CO2 and 1.17g H2O upon combustion. What is the empirical formula of ascorbic acid?

in progress 0
Dâu 4 years 2021-07-16T03:33:24+00:00 1 Answers 16 views 0

Answers ( )

  1. Latifah
    0
    2021-07-16T03:34:36+00:00
    Reply

    Answer:

    C₃H₄O₃

    Explanation:

    The empirical formula is the simplest whole-number ratio of atoms present in a molecule. To solve this question we must find the moles of CO2 = Moles of Carbon and moles of H2O = 1/2 moles H.

    With the difference in masses of the atoms we can find the mass of ascorbic acid and its moles as follows:

    Moles CO2 = Moles C -Molar mass: 44.01g/mol-

    4.31g CO2 * (1mol / 44.01g) = 0.0979 moles C * (12.01g/mol) = 1.18g C

    Moles H2O -Molar mass: 18.01g/mol

    1.17g H2O * (1mol / 18.01g) = 0.0650 moles H2O * (2mol H / 1mol H2O) = 0.130 moles H = 0.13g H

    Moles O:

    Mass O: 2.87g-0.13g H – 1.18g C = 1.56g O

    Moles O:

    1.56g O * (1mol/16g) = 0.0975 moles O

    Dividing each number of moles of atoms in the moles of Oxygen (The lower number of moles:

    O/O = 0.0975 moles O/0.0975 moles O = 1

    H/O = 0.130 moles H/ 0.0975 moles O = 1.333

    C/O = 0.0979 moles C/ 0.0975 moles O = 1

    As empirical formula requires whole-numbers we need to multiply this ratio 3 times:

    O = 1*3 = 3

    H = 1.333*3 = 4

    C = 1*3 = 3

    Empirical formula of ascorbic acid is:

    C₃H₄O₃

Leave an answer

Browse

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