1. The Development of Atomic Models
5.1
The Development of Atomic Models
Rutherford’s atomic model could not explain the ___________ ___________ of elements.
Rutherford’s atomic model could not explain why objects ______________ ___________ when _____________.
Rutherford’s model fails to explain why objects change color when heated. As the temperature of this horseshoe is increased, it first appears black, then red, then yellow, and then white. The observed behavior could be explained only if the atoms in the iron gave off light in specific amounts of energy. A better atomic model was needed to explain this observation.

2. The Development of Atomic Models
5.1
The Development of Atomic Models
The timeline shows the development of atomic models from _________ to _________.
These illustrations show how the atomic model has changed as scientists learned more about the atom’s structure.

3. The Development of Atomic Models
5.1
The Development of Atomic Models
The timeline shows the development of atomic models from ___________ to ___________.
These illustrations show how the atomic model has changed as scientists learned more about the atom’s structure.

4. 5.1
The Bohr Model
Bohr proposed that an _____________ is found __________ in ____________ ______________ _____________, or _____________, around the nucleus.

5. Each possible electron orbit in Bohr’s model has a fixed energy.
5.1
The Bohr Model
Each possible electron orbit in Bohr’s model has a fixed energy.
The fixed energies an electron can have are called ___________ ____________.
A __________ of energy is the amount of energy required to _______ an __________ from _________ ________ ____________ to __________ __________ ___________.

6. 5.1
The Bohr Model
Like the rungs of the strange ladder, the energy levels in an atom are not _____________ __________________.
The higher the energy level occupied by an electron, the ________ energy it takes to move from that energy level to the next higher energy level.
These ladder steps are somewhat like energy levels. In an ordinary ladder, the rungs are equally spaced. The energy levels in atoms are unequally spaced, like the rungs in this ladder. The higher energy levels are closer together.

7. The Quantum Mechanical Model
5.1
The Quantum Mechanical Model
The quantum mechanical model determines the _________ ___________ an electron can have and how likely it is to find the electron in various _______________ around the nucleus.
The modern description of the electrons in atoms, the quantum mechanical model, comes from the mathematical solutions to the Schrödinger equation.

8. The Quantum Mechanical Model
5.1
The Quantum Mechanical Model
The propeller blade has the same probability of being anywhere in the blurry region, but you cannot tell its location at any instant. The __________ ________________of an atom can be compared to a spinning airplane propeller.
The electron cloud of an atom is compared here to photographs of a spinning airplane propeller. a) The airplane propeller is somewhere in the blurry region it produces in this picture, but the picture does not tell you its exact position at any instant. b) Similarly, the electron cloud of an atom represents the locations where an electron is likely to be found.

9. The Quantum Mechanical Model
5.1
The Quantum Mechanical Model
In the quantum mechanical model, the probability of finding an ______________ within a certain volume of space surrounding the nucleus can be represented as a fuzzy cloud. The cloud is more dense where the probability of finding the electron is high.
The electron cloud of an atom is compared here to photographs of a spinning airplane propeller. a) The airplane propeller is somewhere in the blurry region it produces in this picture, but the picture does not tell you its exact position at any instant. b) Similarly, the electron cloud of an atom represents the locations where an electron is likely to be found.

10. 5.1
Atomic Orbitals
An _______ ____________ is often thought of as a ________ of ___________ in which there is a ________ _________of __________ an _________________.
Each energy _______________ corresponds to an orbital of a different _________, which describes where the electron is likely to be found.

11. 5.1
Atomic Orbitals
Different __________ ____________ are denoted by letters. The s orbitals are spherical, and p orbitals are dumbbell-shaped.
The electron clouds for the s orbital and the p orbitals are shown here.

12. 5.1
Atomic Orbitals
____________ of the ____________ d orbitals have the same shape but different orientations in space.
The d orbitals are illustrated here. Four of the five d orbitals have the same shape but different orientations in space. Interpreting Diagrams How are the orientations of the dxy and dx2 – y2 orbitals similar? How are they different?