This problem is providing a chemical equation between two hypothetical elements, X and Y and asks for the moles of X that are needed to produce 21.00 moles of D in excess Y. After the following work, the answer turns out to be 15.75 mol X:
<h3>Mole ratios:</h3><h3 />In chemistry, one the most crucial branches is stoichiometry, which allows us to perform calculations with grams, moles and particles (atoms, molecules and ions). It is based on the concept of mole ratios, whereby the moles of a specific substance can be converted to moles of another one, say product to reactant, reactant to reactant, reactant to product and product to product.
<h3>Calculations:</h3>In such a way, since 21.00 moles of D are given, we need the mole ratio of D to X in order to get the answer, which according to the reaction is 3:4 based on their coefficients in the reaction. Hence, we calculate the required as follows:
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