Answer :
Final answer:
The empirical formula of the compound is K1Cr1, indicating a 1:1 ratio between potassium and chromium.
Explanation:
The empirical formula of a compound is determined by finding the simplest whole number ratio of atoms present in the compound. To find the empirical formula, we need to find the moles of each element in the given sample. We can use the molar masses of the elements to convert the grams of each element into moles.
In this case, the sample is composed of 26.5 g of potassium, 35.4 g of chromium, and 38.1 g of an unknown element. We can use the molar mass of each element to convert the grams into moles:
- Moles of potassium: 26.5 g / 39.10 g/mol = 0.677 mol
- Moles of chromium: 35.4 g / 52.00 g/mol = 0.681 mol
- Moles of unknown element: 38.1 g / molar mass
Next, we need to find the mole ratio of each element by dividing the mole value of each element by the smallest mole value. In this case, the smallest mole value is 0.677 mol:
- Mole ratio of potassium: 0.677 mol / 0.677 mol = 1
- Mole ratio of chromium: 0.681 mol / 0.677 mol = 1.007
- Mole ratio of unknown element: 0.681 mol / 0.677 mol = 1.006
Since the mole ratios for all elements are close to 1, we can conclude that the empirical formula of the compound is K1Cr1. The compound is composed of potassium and chromium in a 1:1 ratio.