Stoichiometric Calculations – The Plan Write the chemical equation. Balance the chemical equation. Follow steps to dimensional analysis: Start with what is given. Set up a series of equivalent measures. End with your goal. Solve the problem by cancelling units. Record the appropriate answer with units. 1
Stoichiometric Calculations – The Problem Lithium hydroxide is used in an outer space environment to remove excess exhaled carbon dioxide from the living environment. The products of the reaction are lithium carbonate and water. If 48.0 grams of lithium hydroxide are used in a small scale experimental device, how much carbon dioxide will the device process? The Plan: Write the chemical equation. Balance the chemical equation. Follow steps to dimensional analysis: Start with what is given. Set up a series of equivalent measures. End with your goal. Solve the problem by cancelling units. Record the appropriate answer with units. * Remember Significant Figures. 2
Stoichiometric Calculations – The Plan 1. Write the chemical equation. LiOH + CO2 (g) Li2CO3 + H2O (g) 2. Balance the chemical equation. 2 LiOH + CO2 (g) Li2CO3 + H2O (g) 3
Stoichiometric Calculations – The Plan Follow steps to dimensional analysis: 48.0 g LiOH X 1 mole LiOH X 1 mole CO2 X 44.009g CO2 = 1 23.948 g LiOH 2 mole LiOH 1 mole CO2 2 LiOH + CO2 (g) Li2CO3 (g) + H2O (g) 4
Stoichiometric Calculations – The Answer When 48.0 grams of lithium hydroxide are available for use in a reaction, 44.1 grams of carbon dioxide can be processed by the reaction. *Remember the significant figures. 5