I SOTOPES All atoms of the same element have the same physical and chemical properties But they…

ISOTOPESISOTOPES

All atoms of the same element have the same physical and chemical properties

But they are not all identical

The number of protons of an element must be identical for those atoms to be identified as that element

The number of neutrons can be different

11 H 2

1 H 31 H

1

Learning Task

Workbook page 1, 2 and 5

3

12 p+12 p+12 n12 n

12 e-

50 p+50 p+68 n68 n

50 e-

Mg Sn

ENERGY LEVEL ENERGY LEVEL DIAGRAMSDIAGRAMS

________________________

________________________

________________________

S Cl Mg

16 p+16 n

17 p+18 n

12 p+12 n

682

782

282

• First 3 energy levels, max number of electrons that can be represented are:

• 1st = 2, 2nd = 8, 3rd = 8, 4th? , 5th?

• Electrons in the highest energy level are called valence electrons.

4

COMPOUNDSCOMPOUNDS

can be separated into simpler substances by chemical but not physical means i.e. heating

Compounds are composed of elements combined together

Salt - NaCl

5

IONS - ALL ABOUT STABILITYIONS - ALL ABOUT STABILITY

Happy atoms are stable ions. They do not normally change their structure

Unhappy atoms are unstable. They want to change their structure by:

Giving away an electron or electrons

Taking an electron or electrons

6

IONSIONS

Atoms like to have their electrons in full energy levels

Atoms that have a nearly full outer energy level like to take electrons from other atoms

Atoms that have only one or two electrons in their outer energy level like to give away electrons

7

ION FORMATION ION FORMATION EXAMPLEEXAMPLE

12 p+12 n

Mg

2e-8e-2e-

12+12-0

8

ION FORMATION EXAMPLE – ION FORMATION EXAMPLE – MAGNESIUM ION MAGNESIUM ION

12 p+12 n

Mg2+

2e-8e-

12+10-2+

9

FORMATION OF THE CHLORIDE IONFORMATION OF THE CHLORIDE ION

17 p+18 n

Cl

2e-8e-7e-

17+17-0

10

FORMATION OF THE CHLORIDE IONFORMATION OF THE CHLORIDE ION

17 p+18 n

Cl-

2e-8e-

17+18-1-

8e-

11

DRAWING ENERGY LEVEL DIAGRAMS DRAWING ENERGY LEVEL DIAGRAMS FOR IONSFOR IONS

Mg

_____________________

Ca

_____________________

_____________________

____________________________

Na F

282

2882

182

72

12p+12n

11p+12n

9p+10n

20p+20n

82

882

82

82

2+ 2+ 1+ 1-

12

IONS CONTINUEDIONS CONTINUED

Metals __________ electrons to form __________ ions.

Non-metals __________ electrons to form ___________ ions.

The names of negative ions end in ______

What happens to the names of metallic ions?

give awaypositive

acceptnegative

ide

nothing

13

NAMING IONSNAMING IONS

Positive ions - same name as atom

Negative ions - ending is changed to ‘ide’

ie. Fluorine gains an electron and becomes fluoride

14

LEARNING ACTIVITIESLEARNING ACTIVITIES

Complete energy level diagrams on pages 3 & 4 of your workbook

Page 6 and 7 on ions!

15

SECTION 1.5 – SECTION 1.5 – CLASSIFYING CLASSIFYING COMPOUNDSCOMPOUNDS

16

FORMATION OF IONIC FORMATION OF IONIC COMPOUNDSCOMPOUNDS17

COMPOUNDSCOMPOUNDS

Metals and non-metals combine to form _________ compounds.

If a compound formula begins with a metal or the ion NH4

+ it is an ___________ compound.

ionic

ionic

18

NAMING BINARY IONIC COMPOUNDSNAMING BINARY IONIC COMPOUNDS

Name the metallic ion first, followed by the non-metallic ion ends in “ide”

Ionic compounds always start with metal or an ammonium ion

Write the symbol and charge for each ion

Compounds are electrically neutral - they have no charge - zero.

Use subscripts to equalize the total number of positive and negative charges

19

PREDICTING IONIC PREDICTING IONIC COMPOUND FORMULASCOMPOUND FORMULAS20

(x)Al3+ + (y)O2- =

Na+ Cl-+ = NaCl1+ + 1- = 0

(x)3+ + (y)2- = 0

(x)Al3+ + (y)O2- =

Na+ Cl-+ = NaCl1+ + 1- = 0

(2)3+ + (3)2- = 0

21 PREDICTING IONIC PREDICTING IONIC COMPOUND COMPOUND FORMULASFORMULAS

PREDICTING IONIC COMPOUND PREDICTING IONIC COMPOUND FORMULASFORMULAS

(2)Al3+ + (3)O2- =

Na+ Cl-+ = NaCl1+ + 1- = 0

(2)3+ + (3)2- = 0

Al2O3

22

Alternatively – use the Kriss Kross will make you want to jump, jump method!

MULTIVALENT METALSMULTIVALENT METALS

In groups 3 through 12, many metals form more than one type of charged ion.

Naming is done with the Stock system. The charge on the metallic ion with a number indicating the charge on the ion with Roman numerals

To determine the metal ion’s charge Find the charge of the non-metal ion Determine the charge necessary for the compound

to have no charge Name the compound with a roman numeral in

brackets after the metal ion I.e. tin (IV) chloride

23

MULTIVALENT METALSMULTIVALENT METALS

Fe2O3

The charge on the O is 2-

There are 3 O so there are 6 negative charges

Therefore there needs to be 6 positive charges

There are 2 iron ions so the charge on each is

3+

The name is iron (III) oxide

24

MULTIVALENT METALSMULTIVALENT METALS

PbS

The charge on the sulphide ion is 2-

The charge on the lead ion is then

2+

Lead (II) sulphide

25

IONIC COMPOUNDS COMPOSED OF IONIC COMPOUNDS COMPOSED OF THREE ELEMENTSTHREE ELEMENTS These compounds are composed of a metal or the

ammonium ion combined with a polyatomic ion. (a complex ion)

Most of these ions end in ate or ite

The only positively charged polyatomic ion is ammoniumammonium

Two ions end in ‘ide’ - hydroxide and hydrogen sulfide

26

COMPLEX IONS COMPLEX IONS (POLYATOMIC IONS)(POLYATOMIC IONS)

27

PO53-

perphosphate

PO43-

phosphate

PO33-

phosphite

PO23-

hypophosphite

SO52-

persulfate

SO42-

sulfate

SO32-

sulfite

SO22-

hyposulfite

CO42-

percarbonate

CO32-

carbonate

CO22-

carbonite

CO2-

hypocarbonite

NO4-

pernitrate

NO3-

nitrate

NO2-

nitrite

NO-

hyponitrite

ClO4-

perchlorate

ClO3-

chlorate

ClO2-

chlorite

ClO-

hypochlorite

FORMULAS FOR IONIC COMPOUNDS FORMULAS FOR IONIC COMPOUNDS CONTAINING COMPLEX IONSCONTAINING COMPLEX IONS Write the two ions with their charges

Use subscripts to balance the number of positive and negative charges equal

If a subscript is required for the complex ion put the complex ion in brackets

Examples:

Sodium carbonate

Strotium hydroxide

Tin (IV) sulfite

28

NAMING IONIC COMPOUNDS NAMING IONIC COMPOUNDS CONTAINING COMPLEX IONSCONTAINING COMPLEX IONS Always name the two ions

The first ion is the metal or the ammonium ion

The second ion is the negatively charged complex ion as named on the back of your periodic table.

Examples:

1. FeSO3 (s)

2. Cu2CO3 (s)

3. Cr2(SO4)3 (s)

29

LEARNING ACTIVITIES TO BE LEARNING ACTIVITIES TO BE COMPLETED:COMPLETED: Pages 8-12 all on naming Ionic Compounds!

30