Which of the following is a positively charged subatomic particle? Electron
Neutron
Nucleus
Proton

It’s a proton. “proton: Positively charged subatomic particle forming part of the nucleus of an atom and determining the atomic number of an element.”

Answer- the proton

the proton has a positive charge, the electron has a negative charge, the neutron has a neutral charge, and the nucleus is the center of the atom containing the protons and neutrons

It shows that the experiment is designed properly.

Sink to the bottom. addition of potassium nitrate past it’s dissolution capacity at a particular temperature will cause the extra to just sink to the bottom of the glass.however, if you were to raise the temperature of the solution prior to dissolving it, and then slowly decrease the temperature after the dissolution, you would create a “supersaturated” solution - a solution that has more solute dissolved into it than should be allowed. if you add any extra solute past this, the entire solution would “crystallize,” and this is how you get those cool videos on youtube.