9.1 - Naming Ions

monatomic ion - 1 atom; charge is positive or negative

cation

• positive

• loses electrons

• needs to lose electrons

• metals

anion

• negative

• gain electrons

• needs electrons

• nonmetals

Al is the only common group 3A metal

1A - +1

2A - +2

3A - +3

5A - -3

6A - -2

7A - -1

anion names start with stem of element and end in -ide

many transition metals can form more than 1 cation with different ionic charges

pg 256 - Conceptual Problem 9.1

a. potassium → K+, cation, potassium ion

b. iodine → I-, anion, iodide ion

c. sulfur → S2-, anion, sulfide ion

d. lead, 4 electrons lost → Pb4+, cation, lead (IV) ion

polyatomic ion - composed of more than one atom that are tightly bound and act as unit; positive or negative charge

-ite or -ate → polyatomic ions; negative; -ite indicates one less oxygen than -ate

-ium → polyatomic ions; positive

-ide → monatomic; nonmetals

not suffix for monatomic metals

9.2 - Naming and Writing Formulas for Ionic Compounds

binary compound - 2 or more elements composed of wither ionic or molecular

ionic compound - metal and nonmetal; transfer electron

to name any binary ionic compound, place cation name 1st, followed by anion name

to write the formula, write the symbol of the cation and then anion and use criss cross method

K+ and Cl- → KCl

Ca2+ and Cl- → CaCl2

Mg2+ and O2- → MgO

to write the formula for compounds with polyatomic ions, write the symbol of cation followed by formula for polyatomic ion and criss cross

Ca2+ and (NO3)- → Ca(NO3)2

Li+ and (CO3)2- → Li2CO3

9.3 - Naming and Writing Formulas for Molecular Compounds

molecular compound - nonmetals; can combine in more than 1 way; covalent

1 = mono 2 = di 3 = tri 4 = tetra 5 = penta 6 = hexa 7 = hepta 8 = octa 9 = nona 10 = deca

a prefix in the name of a binary molecular compound tells how many atoms of an element are present in each molecule of the compound

to name binary molecular compounds, use prefixes if needed and end 2nd element with -ide

N2O → dinitrogen oxide

9.4 - Naming and Writing Formulas for Acids and Bases

acid - impound that contains 1 or more H atoms and produces H+ when dissolved in water

HnX

n = indicates number of H+ that are combined with anion

X = mon/poly anion

RULES TO NAME ACID

anion ends in -ide → hydro-(stem)-ic acid

anion ends in -ite → (stem)-ous acid

anion end sin -ate → (stem)-ic acid

HCl → hydrochloric acid

H2SO3 → sulfurous acid

HNO3 → nitric acid

to write acid formulas, use the rules for writing the names of acids in reverse

hydrobromic → HBr

base - compound that produces OH- when dissolved in water

bases are names in the same way as ionic compounds — name of the cation is followed by name of anion

9.5 - The Laws Governing Formulas and Names

law of definite proportions - in samples of any chem compound, masses of the elements are always in the same proportions

MgS

Mg:S

43.13:56.87 = .758:1

law of multiple proportions - whenever the same 2 elements form more than 1 compound, the different masses of 1 element that combine with the same mass of the other element are in the ration of small whole numbers

IONIC CANT BE POLY

ide → binary compound

ite/ate → poly ion that includes O

roman numeral after cation → ionic charge of cation

prefixes → molecular compund