Answer:
The wavelength of the light emitted by a hydrogen atom for the given transition is 2166 nm.
Explanation:
The energy of nth energy levels of the H atom is given as:

Energy of the seventh energy level = 


Energy of the seventh energy level = 


Energy of the light emitted will be equal to the energy difference of the both levels.


Wavelength corresponding to energy E can be calculated by using Planck's equation:


The wavelength of the light emitted by a hydrogen atom for the given transition is 2166 nm.
The answer is A. use casual, friendly conversation.
The correct answer among the choices listed above is option D. The average kinetic energy of water molecules as water freeze <span>decreases as water releases energy to its surroundings. Energy is released as the molecules go into a more condensed phase which is the solid.</span>