Question

The chemical equation below shows the reaction between carbon dioxide (CO₂) and lithium hydroxide (LiOH).

CO₂ + 2LiOH ---> 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?
a. 0.290
b. 0.579
c. 1.16
d. 1.73

Answer 1

To find the required moles of LiOH to react with 25.5 g of CO₂, the mass of CO₂ is converted to moles using its molar mass. The reaction equation indicates that 2 moles of LiOH are needed per mole of CO₂, resulting in 1.16 moles of LiOH needed.The correct option is c.

Step-by-step explanation:

To calculate how many moles of lithium hydroxide (LiOH) are needed to react completely with 25.5 g of carbon dioxide (CO₂), we must first determine the number of moles of CO₂. Using the molar mass of CO₂, which is 44.01 g/mol, we can convert the mass of CO₂ to moles:

Number of moles of CO₂ = mass of CO₂ / molar mass of CO₂ = 25.5 g / 44.01 g/mol = 0.579 moles of CO₂

According to the reaction equation CO₂ + 2LiOH → Li₂CO₃ + H₂O, 1 mole of CO₂ reacts with 2 moles of LiOH. Therefore, to react with 0.579 moles of CO₂, we need:

Number of moles of LiOH = 2 moles of LiOH / mole of CO₂ x 0.579 moles of CO₂ = 1.16 moles of LiOH

So, the correct answer is c. 1.16.