Chemical Formulas represent compounds Chemical formulas are composed

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Chemical Formulas represent compounds.

Chemical Formulas represent compounds.

Chemical formulas are composed of a positive half and a negative half. Ex. -

Chemical formulas are composed of a positive half and a negative half. Ex. - Water is a compound you know to have a formula of H 2 O.

The easiest way to think of writing chemical formulas is to use the oxidation

The easiest way to think of writing chemical formulas is to use the oxidation number (without the + or -) of one element as the subscript of the other element. (look at Periodic Table to get oxidation numbers) +2 -1

Cross over the oxidation numbers without the charges!!! +2 -1

Cross over the oxidation numbers without the charges!!! +2 -1

2 REMINDER: DO NOT write a subscript of 1. Reduce the subscripts if needed.

2 REMINDER: DO NOT write a subscript of 1. Reduce the subscripts if needed.

NAMING COMPOUNDS • Your ability to name compounds and write formula’s hinges on your

NAMING COMPOUNDS • Your ability to name compounds and write formula’s hinges on your ability to recognize whether a compound is Ionic or Molecular.

BINARY IONIC COMPOUNDS • Binary means 2 elements • Ionic means a metal and

BINARY IONIC COMPOUNDS • Binary means 2 elements • Ionic means a metal and a nonmetal (or cation and anion) • Writing Formulas • charges must balance so compound charge is neutral.

BINARY IONIC COMPOUNDS • Writing Formulas from Names • 1 st word = CATION

BINARY IONIC COMPOUNDS • Writing Formulas from Names • 1 st word = CATION • 2 nd word = ANION name with ide ending.

BINARY IONIC COMPOUNDS • Na. Br • Mg. F 2 • Sodium Bromide •

BINARY IONIC COMPOUNDS • Na. Br • Mg. F 2 • Sodium Bromide • Magnesium Fluoride

BINARY IONIC COMPOUNDS • Potassium Chloride • Aluminum Oxide • notice ending of name

BINARY IONIC COMPOUNDS • Potassium Chloride • Aluminum Oxide • notice ending of name is ide! + K Cl -> KCl Al 23+O 32 - -> Al 2 O 3

Polyatomic Ions • Definition bound groups of behave as a unit charge. • Example

Polyatomic Ions • Definition bound groups of behave as a unit charge. • Example , Cl. O 2 • tightly atoms that and carry a 2 SO 3 , NO 2 -

TERNARY IONIC COMPOUNDS • Ternary means 3 different elements • Usually contain Poly-atomic Ions

TERNARY IONIC COMPOUNDS • Ternary means 3 different elements • Usually contain Poly-atomic Ions • Ionic means cation and anion

TERNARY IONIC COMPOUNDS: Writing Formulas • Ca 2+CO 32 - -> Ca. CO 3

TERNARY IONIC COMPOUNDS: Writing Formulas • Ca 2+CO 32 - -> Ca. CO 3 • Calcium Carbonate

TERNARY IONIC COMPOUNDS: Naming • Calcium Nitrate • Ca(NO 3)2

TERNARY IONIC COMPOUNDS: Naming • Calcium Nitrate • Ca(NO 3)2

Naming with Transition Metals • First word = CATION • Second word = ANION

Naming with Transition Metals • First word = CATION • Second word = ANION • You need to determine what charge is on the transition metal if more than one exists.

Naming Transition Metals • Copper (I) Oxide • Cu 2 O

Naming Transition Metals • Copper (I) Oxide • Cu 2 O

Writing Formulas with Transition Metals • Fe. Cl 3 • Fe. Cl 2 •

Writing Formulas with Transition Metals • Fe. Cl 3 • Fe. Cl 2 • Iron (III) Chloride • Iron (II) Chloride

TYPES OF COMPOUNDS • Molecular Compounds • composed of molecules in which elements share

TYPES OF COMPOUNDS • Molecular Compounds • composed of molecules in which elements share electrons. • usually composed of 2 nonmetals. • these elements are attached

MOLECULAR FORMULA • Definition • shows the numbers and kinds of atoms present in

MOLECULAR FORMULA • Definition • shows the numbers and kinds of atoms present in a molecule of a compound. • i. e. CO

TYPES OF COMPOUNDS • Molecular Compounds con’t • Examples CS 2 Si. O 2

TYPES OF COMPOUNDS • Molecular Compounds con’t • Examples CS 2 Si. O 2 BF 3

BINARY MOLECULAR COMPOUNDS • Binary means 2 elements • Molecular means 2 nonmetals •

BINARY MOLECULAR COMPOUNDS • Binary means 2 elements • Molecular means 2 nonmetals • NO ionic charges are present

Naming Binary Molecular Compounds • Prefixes are used to show many atoms are present

Naming Binary Molecular Compounds • Prefixes are used to show many atoms are present in each molecule. • mono, di, tri, tetra, penta, hexa, hepta, octa, nona, deca

Writing Binary Molecular Compounds • CO 2 • no mono prefix is used on

Writing Binary Molecular Compounds • CO 2 • no mono prefix is used on first element • Carbon Dioxide • Di means 2 oxygens!!

Naming Binary Molecular Compounds • 2 ways it’s done! • (prefix + element name)

Naming Binary Molecular Compounds • 2 ways it’s done! • (prefix + element name) i. e. N 2 O monoxide dinitrogen

Naming Binary Molecular Compounds • (prefix + element root + ide) i. e. PCl

Naming Binary Molecular Compounds • (prefix + element root + ide) i. e. PCl 3 Phosphorous Trichloride • All binary compounds end in ide!!!