The mass of 7.11 x 10^24 particles of potassium oxide can be calculated if we know the molar mass of potassium oxide. The molar mass of potassium oxide (K2O) is approximately 94 g/mol. Therefore, the mass of 7.11 x 10^24 particles of potassium oxide can be calculated as follows:
mass = 7.11 x 10^24 particles x 94 g/mol / Avogadro's number
where Avogadro's number is approximately 6.02 x 10^23 particles per mole. The exact mass will depend on the precision of the molar mass and the number of particles.