Answer:
![m_(K_2O)^(by\ K) =3.01gK_2O](https://img.qammunity.org/2021/formulas/chemistry/college/ntpz2qcvf18n843hz1u8cn1h9akt2ieza3.png)
Step-by-step explanation:
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In this case, since 2.50 g of both potassium (molar mass = 39.1 g/mol) and gaseous oxygen (molar mass = 32.0 g/mol) react in a 4:1 and 1:2 mole ratio respectively, to produce potassium oxide (molar mass = 94.2 g/mol), we evaluate the mass of potassium oxide yielded by each reactant in order to identify the limiting one via stoichiometry:
![m_(K_2O)^(by\ K)=2.50gK*(1molK)/(39.1gK)*(2molK_2O)/(4molK)*(94.2gK_2O)/(1molK_2O) =3.01gK_2O\\\\m_(K_2O)^(by\ O_2)=2.50gO_2*(1molO_2)/(32.0gO_2)*(2molK_2O)/(1molO_2)*(94.2gK_2O)/(1molK_2O) =14.7gK_2O](https://img.qammunity.org/2021/formulas/chemistry/college/qythtjmmqdmvrmaguvwmixmdigp5byx1z2.png)
Thus, since the 2.50 g of potassium yields 3.01 g of potassium oxide, we infer it is the limiting reactant and that is the mass of produced product by the reaction.
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