Names and Chemical Formulas of Ionic Compounds

3.2 All about ionic compounds !

Review of ionic compounds: They are between metals and non-metalsThey are between metals and polyatomic

ions! They gain and lose electrons ( a transfer)

Ex: calcium bromide

Today we will learn how to write the names and formulas of ionic compounds

Rules for writing names of ionic compounds

Rules:

The (metal) positive ion is always the first part of the name and its name does NOT change.

Calcium Calcium

The (non-metal) negative ion is always the second part of the name and its name changes.

The non-metal ‘s name changes to the suffix/ending “ide”

Bromine Bromide

If the non-metal is a polyatomic ion, then write its original name with no changes at all

e.g. Ca(NO3)2 calcium nitrate

Practice naming NON-METAL IONSTake off the original ending and add an

“ide” ending. Element Name Ion Name Florine (F)   Sulphur (S)

Write the names of the following ions: a) Br- = __________________________b) Cl- = __________________________c) I- = __________________________d) O-2 = __________________________e) N-3 = __________________________

Write the names for the following ionic compounds:

NaCl LiNO3

CaBr2 Ba3(PO4)2

MgO

KOH

Rules continued

How to write the CHEMICAL FORMULA for the ionic compound????

We need to use the charges/combining capacity for each ion when we do this.

So how does it work?

How to write chemical formulas of ionic compounds

Aluminum Chloride

Potassium Nitride

How to write chemical formulas of ionic compounds

Sodium phosphate

Magnesium oxide

How to write chemical formulas of ionic compounds

Iron(III) oxide

NAMING MONATOMIC METAL IONS

If a metal has more than one possible charge, the charge has to be indicated by a Roman numeral, in parenthesis, immediately following the name.

Ex: Fe+3

Fe+2

Roman numerals are:I 1 V 5 IX 9II 2 VI 6 X 10III 3 VII 7IV 4 VIII 8

P. 86

P. 87

Back to multivalent metals What is the name for

Fe2O3 MnO Hg3N2

p. 89

p. 90

Practice naming with polyatomic ions

Potassium chromate CaSO4

p. 91

HomeworkHomework is to finish all the questions given

in this set of notes.

You should be feeling a little Y Zr (wiser) after this lecture.

Credit to Alexander the great and his gang