Yes they do if that was your question
Answer: 0.600 moles
Balanced eqn for decomposition of the rocket fuel:
2 NH4ClO4 (s) ----> N2 (g) + Cl2 (g) + 2 O2 (g) + 4 H2O (g)
Since, 2 moles of NH4ClO4 produces 2 moles of O2 gas, this means that 0.6 moles of NH4ClO4 will produce 0.6 moles of O2 gas
The refractory period makes the cell rest. In this period, the cell becomes able to depolarize again by collecting ions.
