DrillQuiz

• A molecule CH3Cl is a …. Molecule

• Determine the shape of BF4.

Objective• The student will be able to:

– Recognize and describe precipitates in order to write the names and formulas for the precipitates.

SAT/HSA Enrichment• Which of these substances moves

across cell membranes by osmosis?

a. Saltb. Sugarc. Waterd. Protein

Naming and Writing Naming and Writing Formulas Formulas

for Ionic Compoundsfor Ionic Compounds

Naming and Writing Naming and Writing Formulas Formulas

for Ionic Compoundsfor Ionic Compounds

How do you name ionic How do you name ionic compounds and write their compounds and write their

formulas?formulas?

Naming and Writing Formulas

for Ionic Compounds

• A recipe is a formula for the sauce—a complete list of ingredients and their proportions. Chemistry also uses formulas. Once you know the rules, you can write the formula for any chemical compound.

Binary Ionic Compounds

• These masks are made of an ionic compound with the common name gypsum. This name does not tell you anything about the chemical composition of the compound, though.

Binary Ionic Compounds

• Naming Binary Ionic Compounds– A binary compound is composed

of two elements and can be either ionic or molecular. • To name any binary ionic compound,

place the cation name first, followed by the anion name.

Binary Ionic Compounds

• Tin(II) sulfide, or SnF2, is added to toothpastes to prevent cavities.

Binary Ionic Compounds

• Tin(IV) sulfide, or SnS22,, is used in glazes for porcelain fixtures and dishes.

Binary Ionic Compounds

• Hematite, a common ore of iron, contains iron (III) oxide. The balanced formula is Fe2O3.

Binary Ionic Compounds

• Writing Formulas for Binary Ionic Compounds– Write the symbol of the cation

and then the anion. Add whatever subscripts are needed to balance the charges.

Conceptual Problem

9.2

Conceptual Problem 9.2

Conceptual Problem 9.2

Compounds With Polyatomic Ions

• Write the symbol for the cation followed by the formula for the polyatomic ion and balance the charges.

Compounds With Polyatomic Ions

• For example, calcium nitrate is composed of a calcium cation (Ca2+) and a polyatomic nitrate anion (NO3–). – In calcium nitrate, two nitrate anions,

each with a 1– charge, are needed to balance the 2+ charge of each calcium cation. The formula for calcium nitrate is Ca(NO3)2.

Compounds With Polyatomic Ions

• Oysters produce calcium carbonate to form their shells and sometimes pearls.

Compounds With Polyatomic Ions

• Lead(II)sulfate is an important component of an automobile battery.

Conceptual Problem 9.3

Conceptual Problem 9.3

Conceptual Problem 9.3

Compounds With Polyatomic Ions

• Naming Compounds with Polyatomic Ions– To name a compound containing a

polyatomic ion, state the cation first and then the anion, just as you did in naming binary ionic compounds.

9.2

Compounds With Polyatomic Ions

• Sodium hypochlorite (NaClO) is used as a disinfectant for swimming pools. The metallic cation in this compound is sodium (Na+) so the polyatomic ion must be ClO–.

9.2

Section Quiz1.The correct name for CrCl3 is

a. chromium chlorine.b. chromium(III) chloride.c. monochromium trichloride.d. chromium(III) trichloride.

2.What is the correct formula for strontium nitride?a. Sr3N2

b. SrN2

c. Sr2N3

d. Sr3N

Section Quiz

3.Which one of the following compounds is named correctly?a. sodium chlorite, NaClOb. potassium nitrate, KNO2

c. sodium acetate, NaC2H3O2

d. lithium sulfate, Li2SO3

Section Quiz

Criss-Cross Method• Writing Formulas Worksheet!

– Each student is responsible for 1 or 2 problems.• Be ready to share!

Small-Scale Lab• Chemical Names and Formulas

– Purpose:• Write the chemical names and formulas

of common chemical compounds.• Describe the colors and textures of

common ionic compounds.• Synthesis chemical compounds, and

write their names and formulas.

Summary1. Did we accomplish the objective?

Explain.2. How do ionic compounds form?3. Describe how to determine the names of

binary ionic compounds.4. Describe how to write the formula of

binary ionic compounds.5. Compare and contrast naming binary

and polyatomic ionic compounds. 6. Design a way to remember how to

determine the name of ionic compounds.

Homework• Writing Formulas (Criss-Cross

Method) worksheet– Complete 5 rows