Question

3.50 mol Al(NO3)3 reacts with 5.00 mols K2CrO4, the total number of moles of Al2(CrO4)3 and KNO3 would be?

Here is the equation if it's needed.
2 Al(NO3)3(aq) + 3 K2CrO4(aq) → Al2(CrO4)3(s) + 6 KNO3(aq)

Answer 1

You do this the same way as the last one except this is a limiting reagent problem whereas the last one was not.
Use 3.50 mol Al(NO3)3 and determine mols KNO3.
Do it a second time with 5.00 mols K2CrO4 and calculate mols KNO3 formed.
It is likely the two answers will be different; the correct one in limiting reagent problems is ALWAYS the smaller value and the reagent producing that value is the limiting reagent.
Post your work if you still have questions and explain your trouble spots.