Answer:
To find the empirical formula of the compound, we need to determine the simplest whole-number ratio of atoms in the molecule.
First, we can assume that we have 100 grams of the compound, and calculate the number of moles of each element present in it:
Carbon: 40.8 g / 12.011 g/mol = 3.398 mol
Hydrogen: 5.8 g / 1.008 g/mol = 5.753 mol
Oxygen: 53.4 g / 15.999 g/mol = 3.337 mol
Next, we divide each of these values by the smallest one, which is 3.337, to get the mole ratio:
Carbon: 3.398 mol / 3.337 mol = 1.019
Hydrogen: 5.753 mol / 3.337 mol = 1.723
Oxygen: 3.337 mol / 3.337 mol = 1.000
Rounding these values to the nearest whole number, we get the empirical formula: C1.0H1.7O1.0, which can be simplified to CH1.7O.
To find the molecular formula, we need to know the actual molecular mass of the compound. We can estimate it by adding the atomic masses of the elements in the empirical formula:
Carbon: 1 x 12.011 = 12.011
Hydrogen: 1.7 x 1.008 = 1.714
Oxygen: 1 x 15.999 = 15.999
Total = 29.724 g/mol (approx.)
The molecular mass is close to 180 g/mol, which suggests that the actual molecular formula is a multiple of the empirical formula. Dividing 180 by 29.724, we get a value of about 6.05. Multiplying the subscripts in the empirical formula by this value, we get the molecular formula: C6H10.2O6, which can be further simplified to C3H5.1O3.
The compound with the empirical formula CH1.7O and the molecular formula C3H5.1O3 is commonly known as glyoxylic acid.