Questions: What does homogeneous mean? What do you think this means for the appearance of the solutions that you will use? The mass of a volumetric flask is 40.638 g. After adding 15.0 mL of 95% ethanol and adding enough water to complete the volume to 50.00 mL, the flask weighed 88.219 g. What is the density of the mixture?

Solution Steps

A homogeneous mixture is one that has a uniform composition throughout. This means that the components that make up the mixture are evenly distributed and cannot be distinguished from one another.

For the appearance of the solutions, being homogeneous means that the solution will look the same throughout. There will be no visible separation of components, and the solution will appear as a single phase.

First, we need to determine the mass of the solution. The mass of the empty flask is 40.638 g, and the mass of the flask with the solution is 88.219 g. Therefore, the mass of the solution is: \[ \text{Mass of solution} = 88.219 \, \text{g} - 40.638 \, \text{g} = 47.581 \, \text{g} \]

The volume of the solution is 50.00 mL. Density is defined as mass per unit volume. Therefore, the density of the mixture is: \[ \text{Density} = \frac{\text{Mass of solution}}{\text{Volume of solution}} = \frac{47.581 \, \text{g}}{50.00 \, \text{mL}} = 0.9516 \, \text{g/mL} \]

Final Answer