In the reaction 2RbNO3 → 2RbNO2 + O2, how many moles of O2 are produced when 5.0 mol of RbNO3 decompose?

The balanced equation for the reaction is as follows

2RbNO₃ - - > 2RbNO₂ + O₂

stoichiometry of RbNO₃ to O₂ is 2:1

number of moles of RbNO₃ decomposed - 5.0 mol

when 2 mol of RbNO₃ decomposes, 1 mol of O₂ is formed

therefore when 5.0 mol of RbNO₃ decomposes - 5.0 / 2 = 2.5 mol of O₂

2.5 mol of O₂ is formed