electrons quiz

chem 2023

Aufbau Principle

Electrons occupy lowest energy levels first

Pauli Exclusion Principle

No two electrons can have the same set of quantum numbers, must have opposite spins, and only two per orbital

Hund’s Rule

Every orbital in a sublevel should be occupied with a single electron before orbitals are doubled up

Bohr Model

Proposed the electron is only found in specific circular paths around the nucleus (fixed energy)

Energy levels are not equally spaced (higher energy: closer together)

Model is based on the movement of 1 electron

Drawing a Bohr Model

2 - 8 - 8 -18

Period represents the # of energy levels

The Nature of Light

High energy → Short Wavelength (violet)

Low energy → Long Wavelength (red)

Frequency

The number of wave cycles to pass through a given point in a certain amount of time

Wavelength

Distance between crests

Speed of Light

3.00 × 10⁸ m/s

Calculate wavelength/frequency

3.00 × 10⁸ m/s = Wavelength x Frequency

Planck’s Constant

6.626×10^-34

Calculate Energy

energy = planck’s constant x frequency

Photon

Particle of light with a certain amount of energy

Photoelectric Effect

Electrons gain energy and are ejected from metals when light is shined on them

Heisenberg Uncertainty Principle

It is impossible to simultaneously determine the position AND velocity of an electron

Photons of light can randomly known an electron off course (measure, position, velocity changes)

Double Slit Experiment

Demonstrates the wave-particle duality of light and matter.

It involves shining a beam of particles or light through two closely spaced slits onto a screen. The resulting pattern on the screen shows an interference pattern, indicating that the particles or light waves behave as both particles and waves.

De Broglie’s Contributions

Introduced the idea that particles, such as electrons, could be described not only as particles but also as waves

Quantum Mechanical Model

Based on math

Energy is still quantized

BUT no specific path for the electrons

Schrodinger

Treated electrons as diffuse waves

Based completely on probability

Principal Quantum Number (n)

Number that specifies the properties and locations of electrons in orbital

As n increases, the AVERAGE distance from the nucleus increases (and so does the energy)

Each can hold a different number of electrons

Atomic Orbital

Represent probability of electron location

Threshold Frequency

refers to the minimum frequency of light required to initiate the photoelectric effect

The frequency at which electrons in a material start to be emitted when exposed to light