What molarity of sodium nitrate do you produce from 4 g of nitric acid and 3 g of sodium hydroxide?
Unknowable with the given information.
We can work out the molar quantity from the given masses of the reactants:
Clearly, nitric acid is the limiting reagent. And thus
This question is very artificial inasmuch as it quotes a mass of nitric acid, when it should quote a volume of acid with a given concentration.