Answer: Because new substances are formed.
Explanation: A chemical property is any of a material's properties that becomes evident during, or after, a chemical reaction; that is, any quality that can be established only by changing a substance's chemical identity. Once a chemical change occurs it cannot be undone due to the change in chemical identity. The creation of a new substance is not reversible.
Answer:
Wavelength of the photon depends on transition from different states.
Explanation:
The wavelength of the photon that is emitted from the atom during the transition depends on the transition from different states. If the photon is emitted from n=4 state to n=3 state, the wavelength of photon is 1875 while on the other hand, if the photon is emitted from n=5 state to n=3 state, the wavelength of photon is 1282. If the photon is emitted from n=3 state to n=2 state, the wavelength of photon is 656.