Sublimation is an endothermic transition from the solid state to the gaseous without passing through the liquid phase so YES, it requires energy. Iodine is one example of a substance that will sublime at normal pressure and so are carbon & arsenic.
At a certain temperature and pressure, most substances have what is know as a "triple point". This is where the solid, gas and liquid all occur at the same temperature. It still requires energy to transform one into the other. In other words, if you have a solid, liquid and gas of some substance at the triple point and add energy, some of the solid will become liquid and some of the liquid will become gas but the temperature will remain the same.
Substances which sublime at normal pressures (iodine, carbon & arsenic) are at a pressure which is below their triple point. It still requires energy to move from one state to the other.
Melting chocolate requires energy input because the solid chocolate is transitioning into a liquid state. The energy input breaks the molecular bonds holding the solid together, absorbing energy in the process.
Absorbing energy from the surroundings is endothermic. (The opposite - releasing energy to the surroundings - is exothermic).
Melting is a phase change in which a substance changes from the solid state to the liquid state. Sublimation is a phase change in which a solid moves directly into the gas phase. Both melting and sublimation are two types of physical change.
The three of boiling, melting, and condensation describe matter change of state.Boiling is sate change from liquid to gasmelting is state change from solid to liquidcondensation is state change from gas to liquid
endothermic
Melting chocolate requires energy input because the solid chocolate is transitioning into a liquid state. The energy input breaks the molecular bonds holding the solid together, absorbing energy in the process.
When liquid water freezes, it releases heat to the surroundings. This is because as water cools and freezes, it is converting its energy to a lower state, thereby releasing energy in the form of heat to the surrounding environment.
Absorbing energy from the surroundings is endothermic. (The opposite - releasing energy to the surroundings - is exothermic).
Sublimation of a substance, for example, of frozen carbon dioxide or dry ice, involves the substance's absorbing heat energy from its surroundings. Hence, the dry ice itself gains the energy needed to change from solid to gas, and the surroundings lose the energy, and indeed are perceived as colder. Sublimation of a substance, for example, of frozen carbon dioxide or dry ice, involves the substance's absorbing heat energy from its surroundings. Hence, the dry ice itself gains the energy needed to change from solid to gas, and the surroundings lose the energy, and indeed are perceived as colder.
Chemical energy can be converted into other forms of energy, such as heat, light, or mechanical energy. This transformation usually occurs during chemical reactions when bonds between atoms are broken or formed, releasing or absorbing energy in the process.
Solid to liquid is known as melting, where a solid substance transitions into a liquid state by absorbing heat energy. Liquid to solid is known as freezing, where a liquid substance transitions into a solid state by releasing heat energy.
The two phenomenons are thermodynamics phenomenons involving heat (absorbing or releasing).
The energy used for sublimation and fusion is thermal energy. Sublimation requires the input of heat energy to convert a solid directly into a gas, while fusion involves the heat energy required to overcome the electrostatic repulsion between atomic nuclei to combine them into a new nucleus.
The significance of H in chemical reactions is that it represents the heat energy exchanged between the system and its surroundings at constant pressure. It indicates whether a reaction is exothermic (releasing heat) or endothermic (absorbing heat), and helps determine the overall energy change in the reaction.
Chemical energy is stored in the bonds between atoms and molecules. When chemical reactions occur, these bonds are broken and rearranged, releasing or absorbing energy in the form of heat or light. This energy is then stored in the new bonds that are formed.
The balance of heat energy in the ocean is maintained through various processes such as solar radiation heating the surface, heat exchange with the atmosphere, ocean currents redistributing heat, and mixing of water layers through wind action. The ocean acts as a heat reservoir, absorbing and releasing heat to regulate its temperature and maintain balance.
Absorbing heat means taking in thermal energy from the surroundings, causing a temperature increase in the absorbing material. This process is common in objects or substances that have the ability to absorb and store heat energy.