boil
water
Boiling.
Most of us would call that "freezing", or possibly "solidification" if we're reluctant to say "freezing" about something that might happen well above normal room temperatures.
No
No, liquid nitrogen is not a supercritical fluid. A supercritical fluid exists at a temperature and pressure above its critical point where it displays properties of both a liquid and a gas. Liquid nitrogen remains in the liquid state at low temperatures and normal pressures.
Depends on what you consider normal.
At temperatures below the boiling point, this phase change is evaporation. Above the boiling point, the liquid boils.
Solid to Gas - sublimation/depositing occurs at temperatures below 0.01°C. Solid to Liquid - melting/freezing occurs at temperatures above 0.01°C and below 100°C Liquid to Gas - boiling/condensing occurs at temperatures above 0.01°C and is complete above 100°C
winter
Above 660.3 oC, aluminium is a liquid. Presuming normal atmospheric pressure.
No. Iron is a liquid at temperatures above 2,800 degrees Fahrenheit.
Potassium can be solid, liquid or gas. At normal room temperature and atmospheric pressure it is a solid. Above 63.3oC it is a liquid and above 760oC it is a gas.