I think the correct answer would be the third option. From the physical change that happened, we can only tell that the mass of the plastic would be still the same and would weigh 15 grams. This is in accordance with the Law of conservation of mass where it states that mass cannot be destroyed or created. So, since it is only a physical change that happens the substance itself would still be the same and it is only the form that is changed, it would still have the same mass. However, with the change, the volume is changed and is said to increase which means it would greatly affect the density. Increasing the volume would result to a decrease in density.
I believe that it is petroleum ether.
Answer:
1. <u>No, you cannot calculate the solubility of X in water at 26ºC.</u>
Explanation:
You cannot calculate the solubility of X in <em>water at 26 degrees Celsius </em>because you do not know whether the solution formed by dissolving the crystals in 3.00 liters of water is saturaed or not.
The only way to determine the solubility of the compound X is by dissolving the crystals in certain (measured) amount of water and making sure that some crystals remain undissolved, as a solid on the bottom of the beaker.
Next, you should filter the solution to remove the undissolved crystals. Then, weigh the solution, evaporate, wash, dry, and weigh the crystals.
Then you have the mass of the crystals dissolved and the mass of the solution which will let you calculate the mass of pure water, and then the solubility.
