Here's why:
* Density is mass per unit volume. You'd need a liquid that wouldn't dissolve diphenyl to accurately measure the volume of a known mass.
* Diphenyl is non-polar. Finding a suitable solvent that wouldn't dissolve it would be challenging.
How to determine the density of diphenyl:
1. Water Displacement: Since diphenyl is insoluble in water, you can use the water displacement method. This involves:
* Weighing a known volume of water in a graduated cylinder.
* Carefully adding the diphenyl to the cylinder.
* Measuring the volume change in water.
* Subtracting the initial volume of water from the final volume to find the volume of the diphenyl.
* Dividing the mass of diphenyl by its volume to get the density.
2. Pycnometer: A pycnometer is a special flask used to measure the volume of irregularly shaped solids.
* Weigh the empty pycnometer.
* Fill it with diphenyl.
* Weigh the pycnometer with the diphenyl.
* Fill the pycnometer with water, making sure to displace the diphenyl.
* Weigh the pycnometer with the water.
* Calculate the volume of diphenyl using the weights and known density of water.
* Divide the mass of diphenyl by its volume to get the density.
Remember to be cautious when working with diphenyl as it can be harmful. Always use appropriate safety measures and handle it in a well-ventilated area.
