Q25E - Chemistry (OpenStax)

Question

Yeast converts glucose to ethanol and carbon dioxide during anaerobic fermentation as depicted in the simple chemical equation here:

\({\rm{Glucose}} \to {\rm{Ethanol + Carbon Dioxide}}\)

(a) If \(200.0g\) of glucose is fully converted, what will be the total mass of ethanol and carbon dioxide produced?

 (b) If the fermentation is carried out in an open container, would you expect the mass of the container and contents after fermentation to be less than, greater than, or the same as the mass of the container and contents before fermentation? Explain.

(c) If \(99.7g\)of carbon dioxide is produced, what mass of ethanol is produced?

Step-by-Step Solution

Answer

a.\(200{\rm{g}}\)

b.The mass would decrease.

c.\(102.3{\rm{g}}\)

Step 1. Analyzing for part (a)

According to the law of conservation of mass, mass remains constant.

So, the total mass will remain \(200{\rm{g}}\)

Step 2. Analyzing for part (b)

As the container is open, the carbon dioxide gas will leave the container resulting in a decrease in mass.

Step 3. Finding the mass of ethanol produced

Applying the law of conservation of mass,

\({\rm{Mass of glucose = Mass of ethanol + Mass of Carbon Dioxide}}\)

\(200{\rm{g = Mass of ethanol + 99}}{\rm{.7g}}\)

      Mass of Ethanol = \(102.3{\rm{g}}\)