Lithium hydroxide is used in the space program to remove carbon dioxide (from respiration) in spacecraft. Specifically, lithium hydroxide, LiOH, reacts with carbon dioxide, CO2, to form lithium carbonate, Li2CO3, and water.
2 LiOH + CO2 ® Li2CO3 + H2O
What mass of CO2 can be absorbed by 36 g of LiOH?
a. 14.3
b. 18
c. 33
d. 36
Please assist in solving.
Convert 36 g LiOH to mols LiOH. #mols = grams/molar mass.
Convert mols of what you have (in this case LiOH) to mols of what you want (in this case CO2) using the coefficients in the balanced equation.
Convert mols CO2 to grams CO2. grams = # mols CO2 x molar mass CO2.
Post your work if you get stuck.
14.3
The chemical equation below shows the reaction between carbon dioxide (CO2) and lithium hydroxide (LiOH).
CO2 + 2LiOH mc011-1.jpg Li2CO3 + H2O
The molar mass CO2 is 44.01 g/mol. How many moles of LiOH are needed to react completely with 25.5 g of CO2?
To calculate the mass of CO2 absorbed by 36 g of LiOH, we need to use the balanced equation and stoichiometry.
First, we need to determine the molar mass of LiOH and CO2.
The molar mass of LiOH:
1 lithium (Li) atom = 6.94 g/mol
1 oxygen (O) atom = 16.00 g/mol
1 hydrogen (H) atom = 1.01 g/mol
Therefore, the molar mass of LiOH = (6.94 g/mol) + (1.01 g/mol) + (16.00 g/mol) = 23.95 g/mol.
The molar mass of CO2:
1 carbon (C) atom = 12.01 g/mol
2 oxygen (O) atoms = (16.00 g/mol) x 2 = 32.00 g/mol
Therefore, the molar mass of CO2 = (12.01 g/mol) + (32.00 g/mol) = 44.01 g/mol.
Next, we can calculate the moles of LiOH present in 36 g of LiOH:
Moles of LiOH = Mass of LiOH / Molar mass of LiOH
Moles of LiOH = 36 g / 23.95 g/mol ≈ 1.5 mol
From the balanced equation, we can see that the stoichiometric ratio between LiOH and CO2 is 2:1. This means that 2 moles of LiOH will react with 1 mole of CO2.
Since we have 1.5 moles of LiOH, we can determine the number of moles of CO2 that can be absorbed:
Moles of CO2 = 1.5 mol LiOH x (1 mol CO2 / 2 mol LiOH) = 0.75 mol CO2
Finally, we can calculate the mass of CO2 absorbed using the moles of CO2 and the molar mass of CO2:
Mass of CO2 = Moles of CO2 x Molar mass of CO2
Mass of CO2 ≈ 0.75 mol x 44.01 g/mol ≈ 33.01 g
Therefore, the mass of CO2 that can be absorbed by 36 g of LiOH is approximately 33.01 g.
The correct answer is option c. 33.