Chemist: date: learning objective: the student is able to express the law of conservation of mass quantitatively and qualitatively using symbolic representations and particulate drawings. refer to the synthesis of nitrogen dioxide and the element symbol key: 2no (g) + 1o2 (g) → 2no2 (g) (nitrogen = square, oxygen = circle) given the reactants, use the law of conservation of matter to draw the products: reactants: products: limiting reactant: excess reactant: limiting reactant: excess reactant: draw out the molecular pictures for reactants and products for the reaction of 120 grams of nitrogen monoxide and 96 grams of oxygen. (assume that each molecule drawn represents one mole of the substance.) also, note limiting and excess reactants. refer to the combustion of hydrogen sulfide and the element symbol key: