4.80 L of N2, at 25 ∘C and 1.22 atm , is mixed with 1.80 L of O2, at 25 ∘C and 0.122 atm , and the mixture allowed to react. N2(g)+O2(g)→2NO(g)

How much NO, in grams, is produced?

This is a limiting reagent problem (LR) and you know that because amounts for both reactants are given.

Use PV = nRT to calculate n for N2
Do smae for mols O2.

Using the coefficients in the balanced equation convert mols N2 to mols NO.
Do the same for mols O2 to mols NO.
It is likely that the two values will not agree; in LR problems the correct answer is ALWAYS the smaller value and the reagent responsible for the smaller number is the LR.

Using the smaller value, convert to grams of the product. g = mols x molar mass = ?