When a hydrogen electron makes a transition from n = 2 to n = 1, which of the following statements is true? SELECT ALL THAT APPLY
A. Energy is emitted.
B. Energy is absorbed.
C. The electron loses energy.
D. The electron gains energy.

A. Energy is emittedC. The electron loses energy.

Explanation:

Electron is a sub-atomic particle of the atoms that has a negative charge and is present in the shell of the atom. The shell of the atom is represented by n and each shell has a difference in energy level. When an electron is present in a ground state that means the electron is present in the original shell and as the energy is gained by electron the electron jumps from ground state to higher energy level and called electron in the excited state. When the electron returns to a higher energy level to lower energy then the electron loses energy and the energy is released and forms emission spectra. So when an electron goes to that means electron loses energy because it goes from a higher energy level that is to lower energy level that is .

It is called a neutralization reaction

Adozen is 1221/12 = 1.751.75 x 12 = 21therefore, 1.75 is the answer.