Answer:
See explanation.
Explanation:
For the ideal gas law (PV = nRT), we can notice that when the temperatures increases, the pressure or the volume must increase.
For the container with constant volume, the pressure will increase. Because density is mass/volume, in this container the density will not change.
For the other container, the pressure must be the same as the external, so it will not change, then the volume must increase. When the volume increases, the density decreases (density = mass/volume), so the pressure doesn't change and the density decreases.