Quantum Model of the Atom Electrons in Atoms

Bohr Model Auf Bau – Electrons are placed in the lowest energetically available subshell.

Auf bau

Electron Configuration

What is the maximum number of electrons that can occupy the f orbital? D. 22

A neutral atom has electron configuration 1s22s22p63s23p2 A neutral atom has electron configuration 1s22s22p63s23p2. What element is this? A. carbon B. nitrogen C. silicon D. germanium

A neutral atom has an electron configuration of 1s22s22p63s1 A neutral atom has an electron configuration of 1s22s22p63s1. What is its atomic number? A. 5 B. 11 C. 14 D. 20

How many electrons completely fill the 3rd energy level? B. 14 C. 18 D. 32

What is the electron configuration for Lithium? A. 1s3 B. 1s12s2 C. 1s22s1 D. 1s21p1

The letter designations for the first four orbital quantum numbers with the number of electrons per orbital at each sublevel are: s:2, p:8, d: 18, f: 32 s:1, p:3, d: 5, f: 7 s:2, p:6, d: 10, f: 14 s:1, d:6, p:10, f: 14

D. none of the given answers A neutral atom has an electron configuration of 1s22s22p6. what is the ground state configuration of an element that possesses one more electron? A. 1s22s22p63s1 B. 1s22s22p7 C. 1s22s32p6 D. none of the given answers

S 16e- 1s2 2s2 2p6 3s2 3p4 S 16e- [Ne] 3s2 3p4 Notation Core Electrons Longhand Configuration S 16e- 1s2 2s2 2p6 3s2 3p4 Core Electrons Valence Electrons Shorthand Configuration S 16e- [Ne] 3s2 3p4

Stability Full energy level Full sublevel (s, p, d, f) Half-full sublevel

Stability Electron Configuration Exceptions Copper EXPECT: [Ar] 4s2 3d9 ACTUALLY: [Ar] 4s1 3d10 Copper gains stability with a full d-sublevel.

Stability Electron Configuration Exceptions Chromium EXPECT: [Ar] 4s2 3d4 ACTUALLY: [Ar] 4s1 3d5 Chromium gains stability with a half-full d-sublevel.

Stability 1+ 2+ 3+ NA 3- 2- 1- Ion Formation Atoms gain or lose electrons to become more stable. Isoelectronic with the Noble Gases. 1+ 2+ 3+ NA 3- 2- 1-

O2- 10e- [He] 2s2 2p6 Stability Ion Electron Configuration Write the e- config for the closest Noble Gas EX: Oxygen ion  O2-  Ne O2- 10e- [He] 2s2 2p6

The electron configuration of CL- is : a. [Ne] 2s22p6 b. [Ne] 3s23p5 c. [Ne] 2s23p6 d. [Ne] 3s23p6

The electron configuration of sILVER is : a. [Kr] 5s25d9 b. [Kr] 5s24d10 c. [Kr] 5s14d10 d. [Kr] 5s24d9

The electron configuration of the ion that Potassium forms is: a. [Ne] 3s23p6 b. [Ar] 4s2 c. [Ar] 4s1 d. [Ar] 4s24p6

The electron configuration of the ion formed when te gains stability is: a. [Kr] 5s24d105p4 b. [Xe] 5s24d105p6 c. [Kr] 5s25d105p6 d. [Kr] 5s24d105p6

Orbits vs. orbitals

Radial Distribution Curve Quantum Mechanics Orbital (“electron cloud”) Region in space where there is 90% probability of finding an e- Orbital Radial Distribution Curve

Heisenberg Uncertainty Principle Impossible to know both the velocity and position of an electron at the same time

S and p orbitals

Schrodingher’s cloud models

D orbitals

If the accuracy in measuring the position of a particle increases, the accuracy in measuring its velocity will: A. increase B. decrease C. remain the same D. be uncertain

The reason the position of a particle cannot be specified with infinite precision is the: A. exclusion principle. B. uncertainty principle. C. photoelectric effect. D. principle of relativity.

Quantum Numbers Four Quantum Numbers: Specify the “address” of each electron in an atom UPPER LEVEL

Quantum Numbers 1. Principal Quantum Number ( n ) Main Energy level Size of the orbital

f d s p Quantum Numbers 2. Angular Momentum Quantum # ( l ) Energy sublevel Shape of the orbital f d s p

Quantum Numbers 3. Magnetic Quantum Number ( ml ) Orientation of orbital (x,y,z) Specifies the exact orbital within each sublevel

Quantum Numbers px py pz

A spherical electron cloud surrounding an atomic nucleus would best represent: A. an s orbital B. a px orbital C. a px and py orbital D. a d orbital

Which orbitals are dumbbell shaped along the x, y and z axis? A. s B. p C. d D. f

2s 2px 2py 2pz Quantum Numbers Orbitals combine to form a spherical shape. 2s 2pz 2py 2px

Quantum Numbers n = # of sublevels per level n2 = # of orbitals per level Sublevel sets: 1 s, 3 p, 5 d, 7 f

Quantum Numbers 4. Spin Quantum Number ( ms ) Electron spin  +½ or -½ An orbital can hold 2 electrons that spin in opposite directions.

How many quantum numbers are used to describe the energy state of an atom?

Quantum Numbers Pauli Exclusion Principle 1. Principal #  No two electrons in an atom can have the same 4 quantum numbers. Each e- has a unique “address”: 1. Principal #  2. Ang. Mom. #  3. Magnetic #  4. Spin #  energy level sublevel (s,p,d,f) Orbital (X,Y,Z) Electron (+1/2, -1/2)

The quantum number that indicates the position of an orbital about the three axes in space is: A. principal B. angular momentum C. magnetic D. spin

How many different orbital shapes can an f sublevel have?

The spin quantum number indicates that maximum capacity for electrons within an orbital is:

The principal quantum number, n, determines the ____________ of the orbital A. Orientation B. Energy C. Shape D. Capacity

How many possible electron orientations are there in the 4d orbital?

Each orbital can hold TWO electrons with opposite spins.

WRONG RIGHT Hund’s Rule Orbitals of equal energy must each possess one electron before any can possess a second. “Empty Bus Seat Rule” WRONG RIGHT

Orbital Diagram Electron Configuration 1s2 2s2 2p4 1s 2s 2p O 8e-

S 16e- 1s2 2s2 2p6 3s2 3p4 Dot structure Core Electrons Longhand Configuration S 16e- 1s2 2s2 2p6 3s2 3p4 Core Electrons Valence Electrons

Dot structure Cl P

Feeling overwhelmed? Read Chapter 10