It should be a chemical change
Answer:
carbon dioxide CO₂
Explanation:
Each gas has a characteristic boiling point. You can separate a random sample of gases by gradually cooling the sample until each component gas liquifies. Some compounds, such as CO₂ never liquify. Instead, they turn directly into solids.
The first blank can be filled with the Heliocentric model, and the second blank can be filled with Copernicus.
The heliocentric model known as heliocentrism was proposed by the Renaissance astronomer, mathematician, and the Catholic cleric Nicolaus Copernicus resulting in the Copernican revolution.
It is the astronomical model, in which the planets and the Earth revolve around the Sun positioned at the middle of the Solar system. Factually, the heliocentric model was in contrast to geocentrism, in which Earth is positioned at the center of the Solar system.
It is called permafrost :)