Chem 5.2

What did Bohr propose about electron energy levels?

Electrons are restricted to certain energy levels called orbits, labeled by a quantum number 𝑛n.

What is the excited state of an atom?

A higher energy level (𝑛=2,3,4...n=2,3,4...) that an electron jumps to after absorbing a specific amount of energy.

What is the ground state of an atom?

The lowest energy level (𝑛=1), which is closest to the nucleus.

When does an atom emit light?

When an electron falls from excited state to lower energy level.

What was de Broglie's hypothesis?

Matter acts like waves; electrons move like waves.

What does the Heisenberg Uncertainty Principle state?

Cannot know both position and momentum of an electron exactly.

What did Schrödinger do?

Created math equation for electron as a wave → Quantum Mechanical Model.

What is an electron cloud?

Blurry region where electron probably is. Dense = high probability.

What is an atomic orbital?

Region around nucleus where electron is likely to be found.

Name the four orbital types and their shapes.

s (spherical), p (dumbbell), d (complex), f (complex).

How does electron energy change as 𝑛 increases?

Energy increases.

Sublevels for 𝑛=1,2,3,4n=1,2,3,4?

n=1: 1s; n=2: 2s,2p; n=3: 3s,3p,3d; n=4: 4s,4p,4d,4f

How many orbitals in s, p, d, f?

s=1, p=3, d=5, f=7

Max electrons in s, p, d, f?

s=2, p=6, d=10, f=14

What are the two electron spins?

Clockwise and counter-clockwise.

What is the Pauli Exclusion Principle?

Each orbital holds max 2 electrons with opposite spins.