Question

Measurements show that unknown compound x has the following composition: element mass % carbon 62.1% hydrogen 10.5% oxygen 27.6% write the empirical chemical formula of x.

Answer 1

To write the empirical formula from the percent composition of a compound, assume a 100 g sample, convert grams to moles, divide the moles by the smallest number obtained, and express as a ratio of whole numbers.

Step-by-step explanation:

To determine the empirical formula of a compound with a given percent composition, follow these steps:

1. Assume a 100 g sample of the compound, which turns percentages into grams directly.
2. Convert the mass of each element in grams to moles using the atomic mass of each element (from the periodic table).
3. Divide all the moles by the smallest number of moles calculated.
4. Round to the nearest whole number to get the ratio of the atoms in the compound.

For example, to find the empirical formula of a compound with 62.1% carbon, 10.5% hydrogen, and 27.4% oxygen:

1. Take 62.1 g of carbon, 10.5 g of hydrogen, and 27.4 g of oxygen.
2. Calculate the moles of each element: C (62.1 g / 12.01 g/mol), H (10.5 g / 1.008 g/mol), and O (27.4 g / 16.00 g/mol).
3. Divide by the smallest number of moles to find the simplest whole number ratio.
4. The result is the empirical formula for the compound, which could be written after determining the specific ratios.

This process yields the empirical formula based on the given elemental percentages.