Writing and Naming Ionic Compounds with Polyions

• What is a polyion?• An ion that gains electrons and other elements (usually oxygen) to

have a complete octet and be stable (unreactive)• For example sulfate,SO4

-2 (not sulfide, S2-)• Show stability using Lewis structure—• 30 valence electrons (5 x 6 valence group 6)• Sulfur is in the middle of the skelatal structure• Place bonding electrons then fill in rest• Two electrons short of an octet for all• Two more electrons come from a metal (an ionic bond) to make it a

2- ion O

O S O

O

Iron II

Fe

Statements about Polyion Compounds

Polyion Compound Structure

O

O S O

O

Ca

Compounds with PolyionsWrite statements about the structure in margin of “Polyions” notes sheet

•Each element has an octet (including Ca with an octet under 2 valence lost)•The nonmetals, S and O, are covalently bonded because the bonds share electrons• The metal, Ca, is ionically bonded to the polyion because electrons are transferred.•The Ca becomes 2+ after losing its two electrons (20 p+ and 18 e- = 2+)•The polyion with a sulfur and 4 oxygens is called “sulfate” (see “Polyion” Chart.•The sulfate has a 2- chart after gaining 2 electrons (28 p+ and 30 e- = 2-)•Polyions are commonly found in foods and cosmetics (see product labels) because they form stable octets with oxygen available in our atmosphere

2+

2-

Pg. 394, 8-12

8. Most/least electronegative

A. K, Sc, Ca

B. Br, F, At

C. C, O, N

Pg. 394, 8-12

9. Ionic, NONpolar covalent, polar covalent

A. S—S

B. S—O

C. S—H

D. S—K

Pg. 394, 8-12

10. Polar covalent bonds

A. Phosphorus, P4

B. Oxygen, O2

C. Ozone, O3

D. Hydrogen fluoride, HF

Ionic/Covalent Bonding WorksheetCOVALENT BONDING IONIC BONDING

H + Cl H Cl Na + Cl Na Cl

1. H + H (H2) 1. K + F

2. F + F (F2) 2. Mg + I

3. O + O (O2) 3. Be + S

4. N + N (N2) 4. Na + O

5. C + O (CO2) 5. Al + Br

6. H + O (H2O)

XXXX

XXXX

XXXX

XX

XXXX XX

XXXX

XX

XX

Pg. 394, 8-12

11. Most/Least polar

A. H—O or H—N

B. H—N or H—F

C. H—O or H—F

D. H—O or H—Cl

Pg. 394, 8-1212. Most/Least ionic

A. Na—O or Na—N

B. K—S or K—P

C. Na—Cl or K—Cl

D. Na—Cl or Mg—Cl

Check Understanding

• What is the term for the type of bond formed when two atoms share outer electrons?

1.covalent

2.hydrogen

3.ionic

4.metallic

Check Understanding

• What is the term for the type of bond formed when one or more electron(s) are transferred?

1.covalent

2.hydrogen

3.ionic

4.metallic

Check Understanding

• Which of the bonds below is nonpolar covalent?

1.H—F

2.Na—Na

3.S—O

4.Cl—Cl

Check Understanding

• Which of the bonds below is ionic?

1.H—F

2.Na—Cl

3.S—O

4.Cl—Cl

Check Understanding

• Which is a model for a polar covalent bond?

1.

2.

3.

4.

Check Understanding

• What is the term for the type of bond shown in the picture?

1.covalent

2.hydrogen

3.ionic

4.metallic

Check Understanding

• What is the correct illustration of a hydrogen bond?

1.

2.

3.

4. 3

2

1

4

Check Understanding

• Which bond is most ionic?

1.H—Cl

2.Na—Cl

3.Mg—Cl

4.Al—Cl

Check Understanding

• Which bond is most polar covalent?

1.H—Cl

2.Cl—Cl

3.C—Cl

4.B—Cl