Practice numerical problems daily. The mole concept is a skill—like riding a bicycle. Once learned, you never forget. Focus on dimensional analysis (tracking your units), and you will solve any problem with confidence.
[ 2H_2 + O_2 \rightarrow 2H_2O ] Interpretation: 2 moles of H₂ react with 1 mole of O₂ to produce 2 moles of H₂O. pw some basic concepts of chemistry