For the reaction NH3+? O2 →? NO+? H2O ,

what is the maximum amount of NO
(30.0061 g/mol) which could be formed from
3.79 g of NH3 (17.0305 g/mol) and 18.63 g of O2 (31.9988 g/mol)?
Answer in units of g

-My first thought was to balance the equation, but I have no idea what to do after that.

1 answer

This is a limiting reagent (LR) problem and the way you know that is that amounts are given for BOTH reactants.

Yes, balance the equation first. It would have been nice to do so and I could check the result.

1. Balance the equation.
2a. Convert 3/79 g N to mols. mols = grams/molar mass = ?
2b. Do the same and convert 18.63 g O2 to mols.

3a. Using the coefficients in the balanced equation, convert mols NH3 to mols of NO.
3b. Do the same and convert mols O2 to mols NO.
3c. It is likely that the two values for mols NO will not agree; the correct value to choose is ALWAYS the smaller value and the reagent responsible for that smaller value is the LR.

4. Convert the smaller value for mols NO to g NO. g NO = mols NO x molar mass NO = ?

Post your work if you get stuck.