Question

Determine the empirical formula of a compound consisting of 33.5 g of potassium (K) and 6.85 g of oxygen (O). Insert the appropriate subscripts as needed in the empirical formula.

Empirical formula: _________ (e.g., KO)

Fill in the blank with the correct empirical formula

Answer 1

The empirical formula of the compound is KO.

Step-by-step explanation:

To determine the empirical formula of a compound, we need to find the smallest whole number ratio of the elements. In this case, we have 33.5 g of potassium (K) and 6.85 g of oxygen (O).

Step 1: Convert the mass of each element to moles. The molar mass of potassium is 39.1 g/mol and the molar mass of oxygen is 16.0 g/mol.

33.5 g K * (1 mol K / 39.1 g K) = 0.856 mol K

6.85 g O * (1 mol O / 16.0 g O) = 0.428 mol O

Step 2: Divide the moles of each element by the smallest number of moles.

K: 0.856 mol K / 0.428 mol O = 2

O: 0.428 mol O / 0.428 mol O = 1

The empirical formula is therefore KO.