How many grams of O₂ are needed to react completely with 28.0 g of Li in the following, 2 Li + O₂ → Li₂O?

Question

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To solve this problem, first, we need to determine the molar masses of the reactants and the stoichiometry of the reaction. The chemical formula given is a bit unconventional, but interpreting "O₂" as a compound made of O, S, U, and B elements, we can calculate its molar mass. However, without specific atomic masses for each element, we'll assume standard atomic masses: O (Oxygen) = 16 g/mol, S (Sulfur) = 32 g/mol, U (Uranium) = 238 g/mol, B (Boron) = 10.81 g/mol (approximated to 11 g/mol for simplicity). The formula seems to indicate one atom of each element, so the molar mass of the compound would be approximately 16 + 32 + 238 + 11 = 297 g/mol.Lithium (Li) has a molar mass of about 6.94 g/mol. Given 28.0 g of Li, the moles of Li are 28.0 g / 6.94 g/mol ≈ 4.03 mol. The reaction shows a 2:1 molar ratio between Li and the compound, meaning we need half as many moles of the compound as Li to react completely, which is 4.03 mol / 2 ≈ 2.015 mol of the compound.To find the mass of the compound needed, we multiply the moles by its molar mass: 2.015 mol * 297 g/mol ≈ 598.455 g. However, given the options provided, none match this calculation directly, suggesting a possible misunderstanding in interpreting the chemical formula or a mistake in the calculation process. Given the options and assuming a direct interpretation error, the closest structured response based on typical stoichiometry and molar mass calculations would be to select an option directly without recalculating, which is not feasible with the provided data and options. Thus, the initial explanation aimed to demonstrate a standard approach to such a problem, but it appears there might be a misunderstanding or typo in the question or options provided. Re-evaluating the approach based on the options given and assuming a simple stoichiometric relationship without the exact molar masses could suggest an idealized or theoretical scenario not directly calculable from the provided information. Therefore, the correct choice would be selected based on theoretical understanding or provided options, which in this context, without exact calculation, defaults to a selection error in explanation.

How Many Grams of O2 Are Needed to React Completely

How Many Grams of O₂ Are Needed to React Completely