Question

a 10.89 g sample of a compound contains 6.95 g of iron, fe, 1.28 g of phosphorus, p, and oxygen, o. calculate the empirical formula for the compound

Answer 1

The compound's empirical formula is Fe3P9O.

Step-by-step explanation:

To determine the empirical formula of a compound, we need to find the ratio of the elements present in the compound. In this case, the compound contains 6.95 g of iron (Fe), 1.28 g of phosphorus (P), and the remaining mass of oxygen (O). To calculate the empirical formula, we first need to convert the masses of the elements to moles by dividing the mass by the molar mass of each element. The molar mass of Fe is 55.845 g/mol, the molar mass of P is 30.974 g/mol, and the molar mass of O is 16.00 g/mol.

Using these values, we can calculate the moles of each element:

• Moles of Fe = 6.95 g / 55.845 g/mol = 0.124 mol
• Moles of P = 1.28 g / 30.974 g/mol = 0.041 mol
• Moles of O = (10.89 g - (6.95 g + 1.28 g)) / 16.00 g/mol = 0.386 mol

Next, we need to find the ratio of the moles of the elements by dividing each value by the smallest value:

• Moles of Fe / Moles of P = 0.124 mol / 0.041 mol = 3
• Moles of O / Moles of P = 0.386 mol / 0.041 mol = 9

Therefore, the empirical formula of the compound is Fe3P9O.

Answer 2

To determine the empirical formula, the masses of iron, phosphorus, and oxygen in the compound are converted to moles, and those values are then divided by the smallest number of moles to find the simplest whole number ratio, resulting in the empirical formula Fe3PO4.

Step-by-step explanation:

Determining the Empirical Formula

To find the empirical formula of the compound, first, we'll convert the masses of each element to moles by dividing by their respective atomic masses. Iron (Fe) has an atomic mass of 55.85 g/mol, phosphorus (P) has an atomic mass of 30.97 g/mol, and oxygen (O) has an atomic mass of 16.00 g/mol. The mass of oxygen can be found by subtracting the mass of iron and phosphorus from the total mass of the compound.

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Next, we'll divide all the mole quantities by the smallest number of moles we found, which is for phosphorus.

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Therefore, the empirical formula of the compound, based on whole number mole ratios, is Fe3P1O4 or simply Fe3PO4.