Question

In a common reaction in living things, glucose combines with oxygen to form carbon dioxide and water vapor. In an experiment on this reaction, the masses of glucose, oxygen, and carbon dioxide are measured. This data table shows the measurements.

What is the mass of the water vapor?

Responses

92 grams
92 grams

108 grams
108 grams

117 grams
117 grams

240 grams
240 grams
Compound Mass
Glucose (reactant) 180 grams
Oxygen (reactant) 192 grams
Carbon dioxide (product) 264 grams
Water vapor (product) ?

Answer 1

To determine the mass of the water vapor produced in the reaction, we can apply the principle of conservation of mass, which states that the mass of the reactants must equal the mass of the products in a chemical reaction.

The equation for the reaction is:

\[ \text{Glucose} + \text{Oxygen} \rightarrow \text{Carbon Dioxide} + \text{Water Vapor} \]

From the data provided:
- Mass of glucose = 180 grams
- Mass of oxygen = 192 grams
- Mass of carbon dioxide = 264 grams
- Mass of water vapor = ?

We can calculate the total mass of the reactants and products:

**Total mass of reactants:**
\[ \text{Mass of glucose} + \text{Mass of oxygen} = 180 \, \text{grams} + 192 \, \text{grams} = 372 \, \text{grams} \]

**Total mass of products (carbon dioxide + water vapor):**
\[ \text{Mass of carbon dioxide} + \text{Mass of water vapor} = 264 \, \text{grams} + \text{Mass of water vapor} \]

Setting the total mass of the reactants equal to the total mass of the products:

\[
372 \, \text{grams} = 264 \, \text{grams} + \text{Mass of water vapor}
\]

To find the mass of the water vapor, we solve for it:

\[
\text{Mass of water vapor} = 372 \, \text{grams} - 264 \, \text{grams} = 108 \, \text{grams}
\]

Thus, the mass of the water vapor produced is **108 grams**.