Answer: The moles of NO produces are 4.22 moles
Step-by-step explanation:
We are given:
Moles of nitrogen dioxide = 12.66 moles
The given chemical equation follows:

By Stoichiometry of the reaction:
3 moles of nitrogen dioxide produces 1 mole of NO
So, 12.66 moles of nitrogen dioxide will produce =
of NO
Hence, the moles of NO produces are 4.22 moles