Polyatomic Ions, Prefixes, and Naming Compounds

Where are metals located on the Periodic Table?

Left and Middle

Do metals gain or lose electrons?

lose

Do metals form cations or anions?

cations

Where are non-metals located on the periodic table?

right

Do non-metals gain or lose electrons?

gain

Do non-metals form cations or anions?

anions

The amount of positive charges (+) are ______ to the amount of negative charges (-) in an ionic compound?

equal

Know what groups form what ion with what charge...

group 1= +1

group 2= +2

group 3= first 2 are +3

group 4= go either way

group 5= -3

group 6= -2

group 7=-1

Ag= Ag+

binary ionic compound

contain 2 elements

The cation is always written ____ in the chemical formula of ionic compounds.

The cation is always written first in formulas and is also named first in the name

How are ionic compounds named?

The cation keeps its same name, but the anion gets the suffix -ide attached to the end of it. (Ex: potassium chloride)

What do the roman numerals represent in a ionic compound name?

determines the charge of the cation (Ex: (III) = +3 charge)

Rules for systematically naming ionic compounds

1. Write the name of the metal in the ionic compound

2. If the metal does not form a predictable ion, add a Roman numeral in parentheses that represents the cation charge of the metal.

3. Change the ending of the non-metal in the ionic compound to -ide.

4. To write the complete name of the ionic compound, write the name of the cation followed by the name of the anion.

What is a polyatomic ion?

ions comprised of more than one element- not binary ionic compounds- they are polyatomic ionic compounds

Know all polyatomic ions

See polyatomic flashcards

Ammonium

NH4 +

Acetate

CH3COO -

Hydroxide

OH -

Peroxide

O2 -2

Cyanide

CN -

Cyanate

CNO -

Thiocyanate

SCN -

Permanganate

MnO4 -

Chromate

CrO4 -2

Dichromate

Cr2O7 -2

Oxalate

C2O4 -2

Carbonate

CO3 -2

Hydrogen carbonate (bicarbonate)

HCO3 -

Nitrate

NO3 -

Nitrite

NO2 -

Hydrogen sulfide

HS -

Sulfate

SO4 -2

Sulfite

SO3 -2

Hydrogen sulfate (bisulfate)

HSO4 -

Hydrogen sulfite

HSO3 -

Phosphate

PO4 -3

Phosphite

PO3 -3

Hydrogen Phosphate

HPO4 -2

Hydrogen Phosphite

HPO3 -2

Dihydrogen phosphate

H2PO4 -

Dihydrogen phosphite

H2PO3 -

Perchlorate

ClO3 -

Chlorite

ClO2 -

Hypochlorite

ClO -

What is a molecular (covalent) compound?

also called a molecule

Atoms do not lose or gain electrons as they do in ionic compounds/ionic bonds. They share electrons and form covalent bonds.

What types of elements are covalent bonds generally formed between?

two non-metals

Know greek prefixes for naming molecular compounds

see flashcards

mono-

one

di-

two

tri-

three

tetra-

four

penta-

five

hexa-

six

hepta-

seven

octa-

eight

nona-

nine

deca-

ten

If combining 2 prefixes to form larger numbers, how would 18 be written?

octadeca-

When is the prefix mono not used?

mono- is not used for the first element in a molecular compound.

Simplified: Molecular compounds are named based off of______ and ionic compounds are named based off of ______.

Molecular compounds use the number of elements in the compound to name the compound denoted by prefixes.

Ionic compounds use the chemical charges to denote anions or cations, but they do not use prefixes to show how many of each element is in the compound. (Ionic compounds have charges!)

What is a hydrate?

A hydrate is an ionic compound that contain water molecules bound to ions of the salt in its crystalline structure. (Appear as dry solids)

How is a hydrate named/indicated?

the word "hydrate" is added onto the end and a prefix is attached to hydrate to indicate how many water molecules the compound contains. The chemical formula and the hydrate are separated by a dot. (Ex: FeCl3 . 6H2O is Iron (III) chloride hexahydrate)