if 68.0g of NH3 react with 304g of F2, how many grams of N2F4 are produced

Answer 1

This is a limiting reagent problem. I know that because amounts are given for BOTH reactants.
1. Write and balance the equation.
2a. Convert g NH3 to moles. moles = grams/molar mass.
2b. Same for g F2.
3a. Using the coefficients in the balanced equation, convert moles NH3 to moles N2F4
3b. Same procedure convert moles F2 to moles N2F4.
3c. Obviously, the numbers are different and both can't be right. The correct value in limiting reagent problems is ALWAYS the smaller one and the reagent producing that value is the limiting reagent.
4. Using the smaller value for moles N2F4 convert moles to grams. g = moles x molar mass.