Ascorbic acid (vitamin c) contains c, h, and o. in one combustion analysis, 5.24 g of ascorbic acid yields 7.86 g co2 and 2.14 g h2o. calculate the empirical formula and molecular formula of ascorbic acid given that its molar mass is about 176 g/mol. add subscripts to complete the formulas.

The answer to your question is:

Empirical formula: C₁ H₁.₃O₁  

Molecular formula:   C₆H₈O₆

Explanation:

Ascorbic acid (C, H, and O)

5.24 g of ascorbic acid

7.86 g of CO2

2.14 g of H2O

Empirical formula = ?

Molecular formula = ?

Molecular mass = 176 g/mol

MW CO2 = 44 g

MW H2O = 18 g

                              44 g of CO2  12 g of C

                             7.86 g of CO2   x

                              x = (7.86 x 12) / 44

                              x = 2.14 g of Carbon

                             18 g of water  2 g of H

                             2.14 g of water   x

                             x = (2.14 x 2) / 18

                             x = 0.24 g of H

Mass of Oxygen = 5.24 - 2.14 - 0.24

Mass of Oxygen = 2.86 g of Oxygen

Moles

                         12 g of C  1  mol

                         2.14 g       x

                         x = 2.14 / 12

                         x = 0.18 moles of Carbon

                        1 g of H 1 mol

                        0.24 g  x

                        x = 0.24 / 1

                        x = 0.24 moles of H

                        16 g of O 1 mol

                        2.86 g      x

                        x = 2.86/ 16

                        x = 0.18 moles of oxygen

Divide by the lowest number of moles

Carbon = 0.18/ 0.18  = 1

Hydrogen = 0.24/0.18 = 1.3

Oxygen = 0.18/0.18 = 1

Oxygen = 0.18 / 0.18

                                       C₁ H₁.₃O₁                                          

Molecular formula

C = 12; H = 1.3 ; O = 16     MW = 29.6

Molar mass/ MW                 176/ 29.6  = 6

                                      C₆H₈O₆

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !