Ch 7 Ions and metallic bonding

Ionic Bonding – electrical attraction between large numbers of cations and anions (metals & nonmetals); forms solid crystals

Octet rule: Atoms tend to achieve a noble gas electron configuration when forming a chemical bond. (oct = 8; s & p orbitals add to 8; ns2p6)

Use electron dots to predict the formulas for the compound formed between

a) Li and Br b) Na and S

see pg. 203

Cation anion formula name

Writing formulas & names

1) Crystalline solids at room temperature *denoted by letter (c) ; 3D crystalline

network; where each cation is surrounded by anions

2) HIGH MELTING POINTS!ex/ NaCl melts at 800 oC (1,474 oF)

3) Conduct electricity if dissolved in water (ions separate) & when in a molten state.

3 properties of ionic compounds

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The chlorine atom gains seven electrons when it becomes an ion.

True or False?

What is the formula for sodium chloride?A) NaClB) ClNaC) Na7Cl1D) SCl

What is the formula for zinc nitride? Zn2+ N3-

A) ZnN B) Zn2N C) Zn3N2

D) ZnN2 E) Zn2N3 F) ZnN3

What is the name given to the electrons in the highest occupied energy level?

A) AnionsB) CationsC) Valence electronsD) Orbital electrons

What is the typical charge of group 2?

A) Negative twoB) Positive twoC) IDKD) Positive one

How many valence electrons does oxygen have?

A) NoneB) OneC) SixD) eight

True or False

A cation is positively charged because it will gain electrons to have a stable electron configuration like a noble gas.

True or False

The name of PbO is lead(II) oxide

Yes or No The charge of an anion is negative.

Please make your selection When an aluminum atom loses its valence electrons, what is the charge on the resulting ion?

a. 2+ b. 3+ c. 2– d. 1+

Please make your selection

The electron configuration of a fluoride ion, F–, is

a. 1s2 2s2 2p5. b. the same as that of the neon atom.

c. 1s2 2s2 2p6 3s1. d. the same as that of a potassium ion.

What is the formula for iron(II) oxide? A) Fe2O3

B) Fe2O2

C) FeOD) Fe3O2

Please make your selection

An ionic compound is

a. electrically neutral.b. composed of anions and cations.

c. held together by ionic bondsd. all of the above 

Please make your selection

Which element when combined with chlorine would most likely form an ionic compound?

a. lithiumb. phosphorusc. oxygend. bromine

What is the formula for cobalt(II) nitrate? A) Co3N2 B) Co(NO3)2 C) Co(NO3)3

Metallic BondsMetallic bonding - between metal atoms;

valence electrons are shared equally in a “sea of electrons”

*This explains the properties of metals!

The valence electrons are mobile and can drift freely from one part of the metal to another.

Electrons are delocalized & gives metals Multidirectional strength (stretching & sheets)

Look at page 209

When a metal is subjected to pressure, the metal cations easily slide past one another (hence malleable & ductile)

• If an ionic crystal is struck with a hammer, the blow tends to push the positive ions close together.

• The positive ions repel one another, and the crystal shatters (brittle).

Sea of electrons

Metal cation

Force Force

Metal cation

Strong

repulsions

Nonmetal anion

Metal Ionic crystal

Which of the following models can describe the valence electrons of metals?

A. A body-centered cube

B. Octets of electrons

C. A rigid array of electrons

D. A sea of electrons