Quantum mechanical model of atoms

What was Schrödingers idea?

He used wave function to describe

amplitude of electron wave as a function of position and time.

Schrödinger experiment?

He pictured the electron as a continuously charged cloud of definite size carrying a charge density that is proportional to square of wave function at any point.

What did Schrödinger equation show

Showed stationary waves of electrons can form around the nucleus of an atom.

Who hypothesised electron wave existence

De broglie

What is an atomic orbital?

function describing shape and regions in space of electrons.

How does an atomic orbital work for electron number of elements

More electrons means more orbitals to fill

What does the 1 in 1s represent

Principal quantum numbers and energy levels of electrons

What does the s in 1s represent

Designates the shape of the orbital

Types of atomic orbitals

s, p, d, f

What are s orbitals

They are spherical and symmetrical around the nucleus, hold only 2 electrons

About the p orbital

It has a dumbbell shape and can be arranged at right angles along x, y and z axis. Holds 6 electrons

What is the d and f orbital

d orbital holds 10 electrons, f orbital holds 14 electrons. They are more complex that the others

What are molecular orbitals

They are formed from pairs of atomic orbitals

What forms sigma bonds

When two s orbitals combine

How is pi bond formed

When two p orbitals combine in the side on geometry

What is a principal quantum number(n)

It defines the energy of electrons

What is orbital quantum number(l)?

Defines the magnitude of angular momentum and the shape of orbital. Falls between 0,1,2, n-1

What is magnetic quantum number

It defines the direction of angular momentum, ranges from -l … l

What is spin quantum number

Defines the magnitude of spin, either -1/2 or +1/2

What is Pauli exclusion principle

No two electrons can have same 4 quantum numbers because orbitals hold 2 electrons

What is Hunds rule

Orbitals in a subshell are occupied singly before doubly

Stern Gerlach experiment

If a beam is passed through a homogeneous field the forces on opposite sides of the poles cancel each other out but in in-homogenous the force on one side is slightly greater

What happens in in-homogenous field

Atoms that pass through will be deflected depending on their momentum

What happens in the experiment

The silver beams used split into two parts

Einstein-de haas experiment

An iron bar is fixed on a string in a solenoid and when current is turned on the bar gets magnetized and turns. Proved effect of spin momentum

Why does the bar turn in Einstein experiment

Because when magnetized magnetic moments and angular momentum are in same direction