An acid can be defined as a substance that yields hydrogen ions (H+) when dissolved in water.

Simple acid naming:If anion name ends with “-ide”Then the acid name is “hydro_______ic acid”

HCl•Pure substance, hydrogen chloride•Dissolved in water (H+ Cl-), hydrochloric acid

An oxoacid is an acid that contains hydrogen, oxygen, and another element.

HNO3 nitric acid

H2CO3 carbonic acid

H2SO4 sulfuric acid

HNO3

HClO3 chloric acid

Formula is written with the H first, then the “other element”, then O

To name these, remember your anion names…

Anion name anion Acid name Acidperchlorate ClO4

- perchloric acid HClO4

chlorate ClO3- chloric acid HClO3

chlorite ClO2- chlorous acid HClO2

hypochlorite ClO- hypochlorous acid HClOsulfate SO4

2- sulfuric acid H2SO4

sulfite SO32- sulfurous acid H2SO3

nitrate NO3- nitric acid HNO3

nitrite NO2- nitrous acid HNO2If the anion ends in “-ate,” the acid ends in “-ic acid”

If the anion ends in “-ite,” the acid ends in “-ous acid”

A base can be defined as a substance that yields hydroxide ions (OH-) when dissolved in water.

NaOH sodium hydroxide

KOH potassium hydroxide

Ba(OH)2 barium hydroxide

NH3 (ammonia) is also classified as a base.

In water, it forms NH4+ (ammonium ion)

and OH- (hydroxide)

Hydrates are compounds with a specific number of water molecules attached.

1) Name compound as usual2) Add “hydrate” with the appropriate Greek

prefix

BaCl2·2H2O barium chloride dihydrate

(in this case, the “mono” prefix is always used.)

Chapter 3

•Atomic mass

•Avogadro’s number, the mole

•Percent composition

•Writing and balancing equations

•Amounts of reactants and products

•Limiting reagents

By definition: 1 atom 12C “weighs” 12.00000 amu

On this scale1H = 1.008 amu (roughly 1/12 carbon)

16O = 16.00 amu

Atomic mass is the mass of an atom in atomic mass units (amu)

amu are sometimes referred to as Daltons (Da)

But, carbon is 12.01!?!?! Where do these atomic masses on the

periodic table come from?

Natural lithium is:

7.42% 6Li (6.015 amu)

92.58% 7Li (7.016 amu)

0.0742 x 6.015 + 0.9258 x 7.016 = 6.941 amu

Atomic masses on the periodic table areaverage atomic masses, over all naturally

occurring isotopes

Average atomic mass of lithium:

Average atomic mass (6.941)

The mole (mol) is the amount of a substance that contains as many elementary entities as there

are atoms in exactly 12.00 grams of 12C

1 mol = NA = 6.0221367 x 1023

Avogadro’s number (NA)

Molar mass is the mass of 1 mole of in gramsdonutsshoes

elephantsatoms

1 mole 12C atoms = 6.022 x 1023 atoms = 12.00 g

1 12C atom = 12.00 amu

1 mole 12C atoms = 12.00 g 12C

1 mole lithium atoms = 6.941 g of Li

For any element atomic mass (amu) = molar mass (grams)

3.2

M = molar mass in g/mol

NA = Avogadro’s number

ORUse dimensional analysis

1 mole atoms = 6.022 x 1023 atoms

1 atom = (atomic mass) amu

1 mole atoms = (atomic mass) g

1 12C atom12.00 amu

12.00 g1 mol 12C atoms

M = molar mass in g/mol

NA = Avogadro’s number

1 mole atoms = 6.022 x 1023 atoms

1 atom = (atomic mass) amu

(molar mass) g = 1 mol atoms

1 mol 12C atoms6.022 x 1023 atoms