How To Find Grams From A Balanced Equation. Thus, one mole of h 2 so 4 weighs 98.08 grams. This is the balanced equation for the reaction.
Calculate the mass of product produced using the moles calculated in step 3 and the gram formula mass of the product: Calculate the mass of unused excess reactant. 4nh 3 + 5o 2 → 4no + 6h 2 o.