Presentation is loading. Please wait.

Presentation is loading. Please wait.

Quantum Theory the modern atomic model. Bohr Model of the Atom a quantum model proposed by Niels Bohr in 1913 It helped to explain why the atomic emission.

Similar presentations


Presentation on theme: "Quantum Theory the modern atomic model. Bohr Model of the Atom a quantum model proposed by Niels Bohr in 1913 It helped to explain why the atomic emission."— Presentation transcript:

1 Quantum Theory the modern atomic model

2 Bohr Model of the Atom a quantum model proposed by Niels Bohr in 1913 It helped to explain why the atomic emission spectrum of hydrogen was not continuous. the neutrons and protons are located in a central region called the nucleus, and the electrons orbit the nucleus much like planets orbiting the Sun.

3 Bohr Model The model worked for hydrogen, but did not work for other elements. It did not explain the chemical behavior of atoms. Therefore, the model was flawed.

4 Louis de Broglie He proposed the idea that electrons have properties of waves (1924). This was another application of the wave- particle theory of light. Because electrons are restricted to a certain space, only certain wavelengths (and energies) are possible.

5 Heisenberg Uncertainty Principle It is impossible to know both the velocity and position of a particle at the same time. The principle puts limits on what can be observed.

6 Erwin Schrödinger He derived an equation that treated an electron like a wave. His model worked well for hydrogen and other atoms. The wave equation predicts a 3-D region around the nucleus (an atomic orbital) where the electron is probably located.

7 The Quantum Mechanical Model Atomic Orbital (“electron cloud”)  Region in space where there is 90% probability of finding an electron Orbital 90% probability of finding the electron

8 Quantum Numbers Principal Quantum Number n Principal Quantum Number ( n ) Angular Momentum Quantum # l Angular Momentum Quantum # ( l ) Magnetic Quantum Number m l Magnetic Quantum Number ( m l ) Spin Quantum Number Spin Quantum Number ( m s )

9 Principal Quantum Number n Principal Quantum Number ( n )  Specifies the principal energy level  Size of the orbital  n 2 = # of orbitals in the energy level 1s1s 2s2s 3s3s

10 Energy sublevels The other quantum numbers determine  shape of the energy sublevel  orientation of the orbital  the exact orbital an electron is located in  the spin of the electron The energy sublevels are labeled as s, p, d, and f. Each sublevel can contain a maximum of 2 electrons.

11 Shapes of s, p, and d-Orbitals

12 Arrangement of sublevels within the levels Level 1 – s only Level 2 – s and p Level 3 – s, p and d Level 4 - s, p, d and f


Download ppt "Quantum Theory the modern atomic model. Bohr Model of the Atom a quantum model proposed by Niels Bohr in 1913 It helped to explain why the atomic emission."

Similar presentations


Ads by Google