Energy level in atom
The energy level of different atoms are different because of the numbers of electron in their outermost shell. The energy of the electron can be change from one energy level to another by disturbing the atom.
Energy level in hydrogen
Ground state energy level Eo:
This is the lowest energy level of an electron in an atom.
Excited state energy level En:
This is the energy level attain by an electron in an atom when electron is disturbed.
Excited energy or excitation energy:
This is the minimum amount of energy that is required to raise the energy level of an atom from the ground state to excited state.
Formula for calculating energy level in atom
E = En – Eo. Where Eo is the energy level of electron in ground state. En is the energy level of the electron in the excited state and E is the energy different between the energy level of the ground state and the excited state.
Energy level chart:
N = 1,2,3,4,5,.......
N represent energy level. Each number represent a particular energy level.
The value of energy level of an atom
The ground state energy level for hydrogen = - 13.6 eV.
Recall that 1 eV (electron volt) = 1.06 * 10⁻¹⁹ Joule.
Therefore, -13.6 eV = -13.6 * 1.06 * 10⁻¹⁹ Joule.
= -21.76 * 10⁻¹⁹ Joule.
Formula for calculating other energy levels of electron in an atom
En = 13.6 eV / n² where n represent the electron quantum number
Work example:
calculate the energy level of an electron when n = 2
solution
En = 13.6 eV / n². n =2, then,
En = 13.6 eV / 2². En = 13.6 / 4. En = 3.4 eV. Let us convert this to joule. Therefore,
1 eV = 1.06 *10⁻¹⁹ Joule. Therefore,
3.4 eV = 3.4 * 1.06 * 10⁻¹⁹ Joule.
= 3.604 joule
Example 2:
Find the energy level between En = 3 and 4
Solution
En = E4 – E3
En = (13.6 eV / 4²) – (13.6 / 3²)
En = (13.6 eV / 16) – (13.6 / 9)
En = 0.85 – 1.51. En = - 0.66 eV
Emission of radiation or spectra
When an atom is heated or excited the electron in the atom gain energy and move from its ground state (lower energy level) to higher state (excited energy level). When the disturbance or heat is removed, the electron releases the heated energy or excitation energy that it received which made the electron to move from ground state to excited state and return back to its ground state. the electron releases this energy in the form of radiation or light.
Photon or quanta
It is a packet of radiation energy that is emitted by a body when its temperature is increased or lowered.
Formula for calculating energy of quanta or photon
E = hf. F is frequency of radiation of photon. Then h is called planck constant. h = .....
Work example
Spectra is the excess energy in the form of radiation emitted by a particle when the is returning from excited to ground state
Equation of radiation energy
Recall that, E = hf and E = En – Eo.
Now let us substitute these formulae into one another, then we will get,
Hf = En – Eo. Also recall that, v = hf (from wave equation)
Let us make f the subject and substitute in the formula above. Therefore,
V = hf. F = v / h. Then,
Hf = En – Eo, h* v/h = En – Eo. Then,
h = h* v / En – Eo.
Where h is planck constant., v is velocity. Eo is ground state energy level and En is excited state energy level.
The energy level of different atoms are different because of the numbers of electron in their outermost shell. The energy of the electron can be change from one energy level to another by disturbing the atom.
Energy level in hydrogen
Ground state energy level Eo:
This is the lowest energy level of an electron in an atom.
Excited state energy level En:
This is the energy level attain by an electron in an atom when electron is disturbed.
Excited energy or excitation energy:
This is the minimum amount of energy that is required to raise the energy level of an atom from the ground state to excited state.
Formula for calculating energy level in atom
E = En – Eo. Where Eo is the energy level of electron in ground state. En is the energy level of the electron in the excited state and E is the energy different between the energy level of the ground state and the excited state.
Energy level chart:
N = 1,2,3,4,5,.......
N represent energy level. Each number represent a particular energy level.
The value of energy level of an atom
The ground state energy level for hydrogen = - 13.6 eV.
Recall that 1 eV (electron volt) = 1.06 * 10⁻¹⁹ Joule.
Therefore, -13.6 eV = -13.6 * 1.06 * 10⁻¹⁹ Joule.
= -21.76 * 10⁻¹⁹ Joule.
Formula for calculating other energy levels of electron in an atom
En = 13.6 eV / n² where n represent the electron quantum number
Work example:
calculate the energy level of an electron when n = 2
solution
En = 13.6 eV / n². n =2, then,
En = 13.6 eV / 2². En = 13.6 / 4. En = 3.4 eV. Let us convert this to joule. Therefore,
1 eV = 1.06 *10⁻¹⁹ Joule. Therefore,
3.4 eV = 3.4 * 1.06 * 10⁻¹⁹ Joule.
= 3.604 joule
Example 2:
Find the energy level between En = 3 and 4
Solution
En = E4 – E3
En = (13.6 eV / 4²) – (13.6 / 3²)
En = (13.6 eV / 16) – (13.6 / 9)
En = 0.85 – 1.51. En = - 0.66 eV
Emission of radiation or spectra
When an atom is heated or excited the electron in the atom gain energy and move from its ground state (lower energy level) to higher state (excited energy level). When the disturbance or heat is removed, the electron releases the heated energy or excitation energy that it received which made the electron to move from ground state to excited state and return back to its ground state. the electron releases this energy in the form of radiation or light.
Photon or quanta
It is a packet of radiation energy that is emitted by a body when its temperature is increased or lowered.
Formula for calculating energy of quanta or photon
E = hf. F is frequency of radiation of photon. Then h is called planck constant. h = .....
Work example
Spectra is the excess energy in the form of radiation emitted by a particle when the is returning from excited to ground state
Equation of radiation energy
Recall that, E = hf and E = En – Eo.
Now let us substitute these formulae into one another, then we will get,
Hf = En – Eo. Also recall that, v = hf (from wave equation)
Let us make f the subject and substitute in the formula above. Therefore,
V = hf. F = v / h. Then,
Hf = En – Eo, h* v/h = En – Eo. Then,
h = h* v / En – Eo.
Where h is planck constant., v is velocity. Eo is ground state energy level and En is excited state energy level.
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