If the electron jumps from the second energy level down to the first energy level, it must give off some energy by emitting light. The atom absorbs or emits light in discrete packets called photons, and each photon has a definite energy.
A.

### What happens when an electron goes to a higher energy level?

It has one electron attached to the nucleus. The energy in a hydrogen atom depends on the energy of the electron. When the electron changes levels, it decreases energy and the atom emits photons. The photon is emitted with the electron moving from a higher energy level to a lower energy level.
• #### What happens when an electron moves from a lower to a higher energy level?

When an electron is hit by a photon of light, it absorbs the quanta of energy the photon was carrying and moves to a higher energy state. Electrons therefore have to jump around within the atom as they either gain or lose energy.
• #### What happens when an electron drops from a higher energy level to a lower one?

When an electron drops from a higher level to a lower level it sheds the excess energy, a positive amount, by emitting a photon. Generally speaking, the excited state is not the most stable state of an atom. In that case the negative energy means a photon (of positive energy) is absorbed.
• #### What is the maximum number of electrons that can be held in the first energy level of an atom?

Thus, the fourth level can hold up to 32 electrons: 2 in the s orbital, 6 in the three p orbitals, 10 in the five d orbitals, and 14 in the seven f orbitals. The sublevels of the first four principal energy levels and the maximum number of electrons that the sublevels can contain are summarized in Table 5.1.
B.

### What causes an electron to change energy levels?

Electrons in atoms and molecules can change (make transitions in) energy levels by emitting or absorbing a photon (of electromagnetic radiation), whose energy must be exactly equal to the energy difference between the two levels.
• #### When electrons are in the lowest energy?

At the lowest energy level, the one closest to the atomic center, there is a single 1s orbital that can hold 2 electrons. At the next energy level, there are four orbitals; a 2s, 2p1, 2p2, and a 2p3. Each of these orbitals can hold 2 electrons, so a total of 8 electrons can be found at this level of energy.
• #### What happens when an electron drops from a higher energy level to a lower one?

When an electron drops from a higher level to a lower level it sheds the excess energy, a positive amount, by emitting a photon. Generally speaking, the excited state is not the most stable state of an atom. In that case the negative energy means a photon (of positive energy) is absorbed.
• #### What is the energy level diagram?

Chemists sometimes use an energy level diagram to represent electrons when they're looking at chemical reactions and bonding. Chemists use the energy level diagram as well as electron configuration notation to represent which energy level, subshell, and orbital are occupied by electrons in any particular atom.
C.

### How do electrons move from a lower energy level to a higher one?

According to Bohr, the amount of energy needed to move an electron from one zone to another is a fixed, finite amount. These zones are known as energy levels (or sometimes called electron shells). At the lowest energy level, the one closest to the atomic center, there is a single 1s orbital that can hold 2 electrons.
• #### What is it called when an atom is in its lowest energy state?

Such configurations are also called energy levels; the atom, or system, is said to undergo a transition between two energy levels when it emits or absorbs energy. The lowest energy level of a system is called its ground state; higher energy levels are called excited states.
• #### What happens to an electron when it absorbs energy?

When an electron absorbs energy, it jumps to a higher orbital. An electron in an excited state can release energy and 'fall' to a lower state. When it does, the electron releases a photon of electromagnetic energy.
• #### What is the maximum number of electrons in the first three energy levels?

Each principal energy level above the first contains one s orbital and three p orbitals. A set of three p orbitals, called the p sublevel, can hold a maximum of six electrons. Therefore, the second level can contain a maximum of eight electrons - that is, two in the s orbital and 6 in the three p orbitals.

Updated: 2nd October 2019