Coal is burned to obtain heat; the chemical products of the combustion are carbon dioxide, water and ash.
After chemical reactions new substances are obtained.
physical changes
Yes, all substances can undergo physical changes. Physical changes do not alter the chemical composition of a substance, but rather change its physical properties such as shape, size, or state (solid, liquid, gas). Examples of physical changes include melting, freezing, boiling, or dissolving.
Chemical changes involve the formation of new substances with different chemical properties, while physical changes involve alterations in the appearance or state of matter without changing the chemical composition. Chemical changes typically involve the breaking and forming of chemical bonds, resulting in new substances with different properties. Physical changes, on the other hand, involve changes in physical characteristics such as shape, size, phase, or state of matter without altering the chemical composition of the substance.
one is photosynthesis. it also loses chlorophyll i do know that. not sure about the other.
Matter can undergo physical changes, such as changes in state (solid, liquid, gas) or shape, without altering its chemical composition. It can also go through chemical changes, resulting in new substances with different properties due to rearrangement of atoms or breaking of chemical bonds. Additionally, matter can experience nuclear changes, like radioactive decay, where the nucleus of an atom changes leading to the formation of different elements.
Structure of what? I'm assuming you're thinking of chemistry, which deals with the structures and chemical composition of substances and the changes they go through...
Yes, rocks in the rock cycle can undergo both physical and chemical changes. Physical changes involve processes like weathering, erosion, and pressure, which can break down rocks into smaller pieces or change their shape without altering their composition. Chemical changes involve processes like melting, crystallization, and metamorphism, which can alter the mineral composition of rocks through reactions with fluids or heat and pressure.
Some substances have stable chemical structures, making it difficult for them to undergo chemical changes. This can be due to strong bonds holding the atoms together or a lack of reactive sites for other substances to interact with. Additionally, factors such as temperature, pressure, and presence of catalysts can also influence the ease of chemical changes in a substance.
The chemical reaction is interrupted.
Decomposition, degradation
Chemical changes generally go more quickly when the temperature increases, and conversely more slowly when it decreases.