C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would...

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Transcript of C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would...

Page 1: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms
Page 2: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

C would like to

N would like to

O would like to

Gain 4 electrons

Gain 3 electrons Gain 2 electrons

Page 3: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Why are electrons

important?

• Chemical bonding involves electrons in the

outermost energy level (valence electrons) .

• When chemical bonds are formed, atoms

gain, lose or share electrons to have 8

electrons in their valence level.

• Known as the Octet Rule (Exception: He

duet rule)

Page 4: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Chemical bonds

• Atoms attempt to fill electron shells.

• When electrons are gained, lost or shared, an

attractive force is formed

called a BOND, which holds elements

together.

-Ionic bonds (metal & non metal)

-Covalent bonds (2 non metals)

-Metallic bonds (2 metals)

Page 5: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Ionic Bonding

• Occurs between a metal and a non-metal.

• Electrons are moved from one atom to another.

• The charged particle that results is called an

ION.

Page 6: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Sodium and Chlorine

Page 7: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms
Page 8: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

IONS

• When an atom loses (or gives away) its

electrons, it becomes a positively charged.

• This is known as a CATION.

• Metals commonly

form positive ions.

Page 9: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

IONS

Continued..

• When an atom gains electrons, it becomes

negatively charged.

• This is known as an ANION.

• Non metals commonly form

negative ions.

Page 10: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Formation of Ions

from Metals

Positive ions form when the number of electrons are

less than the number of protons

Group 1 metals ion 1+

Group 2 metals ion 2+

Group 13 metals ion 3+

Page 11: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Formation of

Sodium Ion

Sodium atom Sodium ion

Na – e Na +

2-8-1 2-8 ( = Ne)

11 p+ 11 p+

11 e- 10 e-

0 1+

Page 12: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Formation of

Magnesium Ion

Magnesium atom Magnesium ion

Mg – 2e Mg2+

2-8-2 2-8 (=Ne)

12 p+ 12 p+

12 e- 10 e-

0 2+

Page 13: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Typical Ions with

Positive Charges

(Cations)

Group 1 Group 2 Group 13

H+ Mg2+ Al3+

Li+ Ca2+

Na+ Sr2+

K+ Ba2+

Page 14: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Fluoride Ion

unpaired electron octet

1 -

: F + e : F :

2-7 2-8 (= Ne)

9 p+ 9 p+

9 e- 10 e-

0 -1

ionic charge

Page 15: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Learning Check

A. Number of valence electrons in aluminum

1) 1 e- 2) 2 e- 3) 3 e-

B. Change in electrons for octet

1) lose 3e- 2) gain 3 e- 3) gain 5 e-

C. Ionic charge of aluminum

1) 3- 2) 5- 3) 3+

Page 16: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Solution

A. Number of valence electrons in aluminum

3) 3 e-

B. Change in electrons for octet

1) lose 3e-

C. Ionic charge of aluminum

3) 3+

Page 17: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Formation of Ions

from Nonmetals

• In ionic compounds, nonmetals in 15, 16, and 17

gain electrons from metals

• Nonmetals gain electrons to achieve a stable octet

• Nonmetal ionic charge: -3, -2, or -1

Page 18: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Ionic Bond

Properties

• Crystal lattice: repeating 3D pattern

Page 19: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Ionic Bond

Properties

• Strong attraction between ions result in

brittleness.

Page 20: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Ionic Bond

Properties

• High melting points & usually solid at room

temperature.

Page 21: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Ionic Bond

Properties

• Soluble

• Good Conductors

Page 22: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Ionic Bonds:

One Big Greedy Thief Dog!

Page 23: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

http://web.jjay.cuny.edu/~acarpi/NSC/salt.htm

Page 24: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

1). Ionic bond – electron from Na is transferred to Cl,

this causes a charge imbalance in each atom. The Na

becomes (Na+) and the Cl becomes (Cl-), charged

particles or ions.

Page 25: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Oxidation

Numbers

• The number of electrons that an element can

lose, gain or share is called the

OXIDATION NUMBER.

• Some elements have more than one

oxidation number, example Fe +2 or Fe+3

Page 26: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Using Oxidation Numbers to

write Ionic Formulas

1. Write the symbols, positive first

2. Put the oxidation number over the top of the

symbol.

3. ‘Criss-Cross’ the numbers to make them

subscripts. (note: if the oxidation numbers are

multiples of each other… reduce before you

‘criss-cross’.

Page 27: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Electrons gained = Electrons lost

Page 28: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Formula Weights

Or

Molecular mass

• Formula weight is the sum of the atomic

masses.

• Example- CO2

• Mass, C + O + O

12 + 16 + 16 = 44

Page 29: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Covalent

Bond • Between 2 or more nonmetal elements.

• Formed by sharing electron pairs.

• Smallest unit of a covalently bonded

compound is called: molecule

• Examples; O2, CO2, C2H6, SiC

Page 30: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Covalent Bond

Properties

• Low melting point & boiling point

• They are not conductors at any state. .

Page 31: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms
Page 32: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Electrons are shared but shared unequally

POLAR COVALENT

BONDS

H2O

Page 33: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Polar Covalent Bonds

Unevenly matched, but willing to share

Page 34: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

polyatomic

ions

A covalently bonded group of atoms acting as one that have a positive or negative charge.

Page 35: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Diatomic

Molecules

• Some elements exist in nature as covalent

bonds.

• Composed of only 2 elements

Page 36: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Diatomic

Molecules

• Nonmetals called the “Heavenly 7”

Page 37: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Heavenly 7

Mnemonic

• HONClBrIF The Chemistry Goose

• Pronounced “Honk-Cool-Brief”

Page 38: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Metallic

Bond

• Formed between atoms of metallic elements

• Metal atoms become cations surrounded by

a pool of electrons

• Good conductors at all states, lustrous, very

high melting points

• Examples; Na, Fe, Al, Au, Co

Page 39: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Metallic Bonds:

Mellow dogs with plenty of bones to go around.

Page 40: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Metallic Bond

Attraction between a metal cation and

shared electrons.

Page 41: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Metals Form

Alloys

• Metals do not combine with metals.

• They form alloys which is a solution of a metal in a metal.

• Examples are steel, brass, bronze and pewter.

Page 42: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

Practice

• Compute the mass of the following compounds

round to nearest tenth & state type of bond:

• NaCl;

• 23 + 35 = 58; Ionic Bond

• C2H6;

• 24 + 6 = 30; Covalent Bond

• Na(CO3)2;

• 23 + 2(12 + 3x16) = 123; Ionic & Covalent

Page 43: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms
Page 44: C would like to N would like to O would like to Bonding Notes for 2016 LS.pdfC would like to N would like to O would like to Gain 4 electrons ... Metallic Bond • Formed between atoms

The End