What is the main difference between the Bohr model and the quantum mechanical model of the atom?

• The Bohr model assumes circular orbits, while the quantum mechanical model uses probability clouds.

• The Bohr model is based on wave functions, while the quantum mechanical model is not.

• The Bohr model describes electron behavior in multi-electron atoms, while the quantum mechanical model does not.

• The Bohr model uses the uncertainty principle, while the quantum mechanical model does not.

According to the passage, what does the electron cloud represent in the quantum mechanical model?

• The probability of finding an electron at a given point around the nucleus.

• The exact path of the electron around the nucleus.

• The energy levels of electrons in an atom.

• The number of electrons in an atom.

How did Louis de Broglie's hypothesis contribute to the development of the quantum mechanical model?

• It suggested that electrons could act as both particles and waves.

• It introduced the concept of electron orbits.

• It explained why electrons emit light when they change direction.

• It solved the problem of electron energy levels.

What is the significance of Heisenberg's uncertainty principle in the context of the quantum mechanical model?

• It states that we cannot know both the momentum and position of an electron simultaneously.

• It explains why electrons emit light when they change direction.

• It describes the exact path of electrons around the nucleus.

• It defines the energy levels of electrons in an atom.

What is an orbital in the context of the quantum mechanical model?

• A three-dimensional region of space with a high probability of finding an electron.

• A circular path that electrons follow around the nucleus.

• A fixed energy level where electrons reside.

• A point where the electron's position is exactly known.