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Chemical reactions involve rearranging atoms to form new substances. In the case of lithium hydroxide (\(\text{LiOH}\)) reacting with carbon dioxide (\(\text{CO}_{2}\)), the products are lithium carbonate (\(\text{Li}_{2}\text{CO}_{3}\)) and water (\(\text{H}_{2}\text{O}\)). This reaction is used in space shuttles to remove \(\text{CO}_{2}\) from the air. By understanding how these compounds interact, we can predict how much \(\text{CO}_{2}\) can be absorbed by a given amount of \(\text{LiOH}\). The equation for this reaction is: \[ 2 \text{LiOH} + \text{CO}_{2} \rightarrow \text{Li}_{2} \text{CO}_{3} + \text{H}_{2}\text{O} \] This balanced equation shows which molecules are involved and in what ratios. Knowing this, we can perform calculations to discover how effectively \(\text{LiOH}\) can scrub unwanted \(\text{CO}_{2}\) from the environment.

Molar mass is essential for converting between grams and moles in stoichiometry. It represents the mass of one mole of a given substance. To find the molar mass of a compound like lithium hydroxide (\(\text{LiOH}\)), sum the atomic masses of its atoms. The atomic masses, typically found on the periodic table, include:

• Lithium (Li) = 6.94 g/mol
• Oxygen (O) = 16.00 g/mol
• Hydrogen (H) = 1.01 g/mol

Adding these values gives us the molar mass of \(\text{LiOH}\): \(6.94 + 16.00 + 1.01 = 23.95\) g/mol. When you know this molar mass, converting mass to moles becomes straightforward, as demonstrated with the initial 83 grams of \(\text{LiOH}\) used in the reaction.

Converting mass to moles allows us to use chemical equations to perform quantitative analyses. This involves the formula: \(\text{moles} = \frac{\text{mass}}{\text{molar mass}}\). For example, converting 83 grams of \(\text{LiOH}\) requires its molar mass, 23.95 g/mol. By dividing: \(\frac{83}{23.95} \approx 3.47\) moles, we understand how much \(\text{LiOH}\) is present in moles. These calculations link mass to the number of atoms or molecules and are fundamental in stoichiometry. Knowing how many moles we have is critical to understanding how substances will react.

Balanced chemical equations are vital in stoichiometry—they ensure mass conservation in reactions. In the reaction \(2\text{LiOH} + \text{CO}_{2} \rightarrow \text{Li}_{2}\text{CO}_{3} + \text{H}_{2}\text{O}\), the coefficients (numbers in front of molecules) indicate the molar ratio of reactants and products. Here, 2 moles of \(\text{LiOH}\) react with 1 mole of \(\text{CO}_{2}\) to produce 1 mole of \(\text{Li}_{2}\text{CO}_{3}\) and 1 mole of \(\text{H}_{2}\text{O}\). When a chemical equation is balanced, it reflects the same number of each type of atom on both sides of the equation, aligning with the law of conservation of mass. This enables us to precisely predict how much of a substance is required or produced during the reaction, aiding in solutions like calculating the mass of \(\text{CO}_{2}\) that can be removed.