Question

An organic compound containing 40% carbon, 6.67% hydrogen and rest of oxygen, has the molecular mass 180g.mol-1. Find out the EF as well as MF of the compound.

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Answer 1

The EF of the compound is CH2O and the MF is C6H12O6.

Step-by-step explanation:

To find the empirical formula (EF) of the compound, we need to determine the simplest whole number ratio of the atoms in the compound. We can assume we have 100 g of the compound, which means we have:

40 g of carbon

6.67 g of hydrogen

53.33 g of oxygen (since the rest of the compound is oxygen)

Next, we can convert the masses to moles:

Moles of carbon = 40 g / 12.01 g/mol = 3.33 mol

Moles of hydrogen = 6.67 g / 1.01 g/mol = 6.61 mol

Moles of oxygen = 53.33 g / 16.00 g/mol = 3.33 mol

We then divide each of the mole values by the smallest number of moles, which is 3.33, to get the simplest whole number ratio:

Carbon: 3.33 / 3.33 = 1

Hydrogen: 6.61 / 3.33 = 1.98 (rounded to 2)

Oxygen: 3.33 / 3.33 = 1

So the EF of the compound is CH2O.

To find the molecular formula (MF), we need to know the molecular mass of the EF. The empirical formula mass (EFM) of CH2O is:

EFM = (1 x 12.01 g/mol) + (2 x 1.01 g/mol) + (1 x 16.00 g/mol) = 30.03 g/mol

We can then calculate the molecular formula mass (MFM) by dividing the given molecular mass (180 g/mol) by the EFM:

MFM = 180 g/mol / 30.03 g/mol = 6

This means the MF is 6 times the EF, or C6H12O6. Therefore