Questions: Sample A is a solid yellow cube with a total mass of 50.0 g. The cube is put into a beaker filled with 250 mL of water. The cube collapses into a small pile of orange powder at the bottom of the beaker. When this powder is filtered out, dried and weighed, it has a total mass of 29.9 g. If the experiment is repeated with 500 mL of water, the powder that's left over has a mass of 30.0 g. - Sample B is 100 mL of a clear liquid. The density of the liquid is measured, and turns out to be 0.77 g/mL. The liquid is then heated in a flask until it boils. The vapor that rises off the boiling liquid is collected for 10 minutes and cooled until it condenses into a separate beaker. The density of the liquid that remains in the flask is then measured, and turns out to be 1.04 g/mL.

Sample A is a solid yellow cube with a total mass of 50.0 g. The cube is put into a beaker filled with 250 mL of water. The cube collapses into a small pile of orange powder at the bottom of the beaker. When this powder is filtered out, dried and weighed, it has a total mass of 29.9 g. If the experiment is repeated with 500 mL of water, the powder that's left over has a mass of 30.0 g.
- Sample B is 100 mL of a clear liquid. The density of the liquid is measured, and turns out to be 0.77 g/mL. The liquid is then heated in a flask until it boils. The vapor that rises off the boiling liquid is collected for 10 minutes and cooled until it condenses into a separate beaker. The density of the liquid that remains in the flask is then measured, and turns out to be 1.04 g/mL.

Transcript text: Sample $\mathbf{A}$ is a solid yellow cube with a total mass of 50.0 g. The cube is put into a beaker filled with 250 mL of water. The cube collapses into a small pile of orange powder at the bottom of the beaker. When this powder is filtered out, dried and weighed, it has a total mass of 29.9 g. If the experiment is repeated with $500 . \mathrm{mL}$ of water, the powder that's left over has a mass of 30.0 g. - Sample B is $100 . \mathrm{mL}$ of a clear liquid. The density of the liquid is measured, and turns out to be $0.77 \mathrm{~g} / \mathrm{mL}$. The liquid is then heated in a flask until it boils. The vapor that rises off the boiling liquid is collected for 10 minutes and cooled until it condenses into a separate beaker. The density of the liquid that remains in the flask is then measured, and turns out to be $1.04 \mathrm{~g} / \mathrm{mL}$.

Solution

Solution Steps

Step 1: Analyze Sample A

Sample A is initially a solid yellow cube with a mass of 50.0 g. When placed in water, it collapses into a pile of orange powder. The mass of the powder is 29.9 g when using 250 mL of water and 30.0 g when using 500 mL of water. The change in mass suggests that part of the original cube dissolves in water, leaving behind a residue. This behavior indicates that Sample A is likely a mixture, as a pure substance would not typically separate into different components under these conditions.

Step 2: Analyze Sample B

Sample B is a clear liquid with an initial density of 0.77 g/mL. Upon heating and boiling, the vapor is collected, and the remaining liquid in the flask has a density of 1.04 g/mL. The change in density after boiling suggests that different components with varying volatilities are present in the liquid. This behavior is characteristic of a mixture, as a pure substance would not exhibit such a change in density upon boiling.