Now that the class understands basic stoichiometry, it is time to move on to molecular conversion between to different elements and or compounds.
Here, Ms.B is explaining the very hard concept to the very attentive students.
Now, in order to convert between different elements and compounds, you must first balance the equation. Then change the substance in to moles to cross the bridge on to the other element. Lastly, you must use the mole ratio in the equation to multiply to the converting element/compound.
Now the students have learned the second level of stoichiometry and are ready to move on to the last one involving limiting and excess reactants.
Just as a side note, when you across the bridge between mole A and mole B, you must remember to round to the nearest hundredth and not take into account any coefficients while determining mass.