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Answer the following question: In a space shuttle, the CO2 that the crew exhales is removed from the air by a reaction within canisters of lithium hydroxide. Let's assume that one astronaut exhales about 825. L of CO2 daily. What mass of water will be produced when this amount reacts with LiOH? The other product of the reaction is Li2CO3. When answering this question include the following:

Have both the unbalanced and balanced chemical equations.
Explain how to find the molar mass of the compounds.
Explain how the balanced chemical equation is used to find the ratio of moles (hint: step 3 in the video).
Explain how many significant figures your answer needs to have.
The numerical answer
Your Answer:

User Coding Edgar
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1 Answer

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Answer:

See Explanation

Step-by-step explanation:

The unbalanced reaction equation is;

CO2(g) + LiOH(aq) + Li2CO3(aq) + H2O(l)

The balanced chemical reaction equation;

CO2(g) + 2LiOH(aq) + Li2CO3(aq) + H2O(l)

The molar mass of each compound is the sum of the relative atomic masses of the atoms of the elements that compose the compounds.

For CO2

12 + 16(2) = 12 + 32 = 44 g/mol

For LiOH

7 + 16 + 1 = 24 g/mol

For Li2CO3

2(7) + 12 + 3(16) = 74 g/mol

For H2O

2(1) + 16 = 18 g/mol

From the balanced chemical reaction equation, the mole ratio is 1:2:1:1. This is obtained from the stoichiometric coefficient of each reactant in the balanced chemical reaction equation.

From the question;

1 mole of CO2 occupies 22.4 L

x moles of CO2 occupies 825 L

x = 1 mole * 825 L/22.4 L

x = 36.8 moles

From the reaction equation;

1 mole of CO2 produces 1 mole of water

36.8 moles of CO2 produces 36.8 moles of water

Mass of 36.8 moles of water = 36.8 moles * 18 g/mol

= 662 g of water

The answer must have three significant figures because that is the same number of significant figures to which values were given in the question.

User Joel Rummel
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