A compound contains potassium, nitrogen, and oxygen. An experimental analysis gave values of 45.942 % potassium and 16.458 % nitrogen, by weight; the remainder is oxygen. What is the empirical formula of the compound? Hint: Assume you have 100 grams of this substance and use moles to relate the mass of one element to another.

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Quizplus · Accepted Answer

The empirical formula of the compound is KNO2.To determine the empirical formula, we assume that we have 100 grams of the compound. This means that we have 45.942 grams of potassium, 16.458 grams of nitrogen, and 37.6 grams of oxygen.We then convert the mass of each element to moles:45.942 g K * (1 mol K / 39.0983 g K) = 1.175 mol K16.458 g N * (1 mol N / 14.007 g N) = 1.175 mol N37.6 g O * (1 mol O / 16.00 g O) = 2.35 mol OWe then divide each of these values by the smallest number of moles to get the simplest whole-number ratio of moles:1.175 mol K / 1.175 mol K = 11.175 mol N / 1.175 mol K = 12.35 mol O / 1.175 mol K = 2Therefore, the empirical formula of the compound is KNO2.

A Compound Contains Potassium, Nitrogen, and Oxygen