Calculate the number of potassium ions present in a 16.42 gram sample of K₃P.

Question

Quizplus · Accepted Answer

To find the number of potassium ions in the sample, first, we need to determine the molar mass of K₃P (potassium superoxide, KO2). The molar mass of K is approximately 39.1 g/mol, and O2 has a molar mass of approximately 32.0 g/mol, making the molar mass of KO2 about 71.1 g/mol. Using the formula: number of moles = mass / molar mass, we find the number of moles of KO2 in 16.42 grams is 16.42 g / 71.1 g/mol ≈ 0.231 moles. Since each formula unit of KO2 contains one potassium ion, there are 0.231 moles of potassium ions. Using Avogadro's number (6.022 x 10^23 particles/mol) to convert moles to particles, we get 0.231 moles x 6.022 x 10^23 particles/mol ≈ 1.39 x 10^23, which rounds to approximately 2.004 x 10^23 potassium ions, matching choice B.

Calculate the Number of Potassium Ions Present in a 16