SCIENCE
PHYSICAL SCIENCES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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It is a chemical reaction, because the kinetic energy of the molecules is changing
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It is a physical reaction, because it is a change of state
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It is a physical reaction, because the density of the material increases
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It is a chemical reaction, because a new form of carbon dioxide is created
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Detailed explanation-1: -Answer and Explanation: The carbon dioxide molecule has zero dipole moment. Therefore the forces that could keep the molecules in liquid or solid phase are very weak. This means that it has a very low boiling point at 1atm 1 a t m pressure (−78.5∘C − 78.5 ∘ C ).
Detailed explanation-2: -Dry ice is basically solidified carbon dioxide and is called so because the gas on solidifying gives an appearance similar to that of ice. Unlike ordinary ice, it does not melt into a liquid but changes directly into CO2gas, a phenomenon known as sublimation.
Detailed explanation-3: -At room temperatures (20-25 oC), carbon dioxide is an odourless, colourless gas, which is faintly acidic and non-flammable. Carbon dioxide is a molecule with the molecular formula CO2. The linear molecule consists of a carbon atom that is doubly bonded to two oxygen atoms, O=C=O.
Detailed explanation-4: -At room temperature, carbon dioxide (CO2) is a colorless, odorless, non-flammable gas, at other temperatures and pressures, carbon dioxide can be a liquid or a solid. Solid carbon dioxide is called dry ice because it slowly changes from a cold solid directly into a gas.