Naming Molecules

Objectives:AHSGE Reading 4.3 Discern organizational

patterns.

3.1 Utilizing electron configurations, Lewis dot structures, and orbital notations to write

chemical formulas

6.1 Predicting ionic and covalent bond types

Other AOD C.2.1 Describe types of covalent bonding between carbon atoms as single,

double, or triple bonds.

• What does “binary” mean?

1. The first element in the formula is named first, using the entire element name.

2. The second element is named second, using the root of the element + the suffix (ending) –ide. (Sounding familiar so far?)

3. Prefixes are use to indicate how many of each element type are in the compound.

4. Don’t use “mono-” before the first element’s name.

Rules for Naming Binary Molecular Compounds

Naming Binary Molecules (continued)

• See Table 9-1 for prefixes.• How would you name N2O?

Answer: dinitrogen monoxide

Common name: nitrous oxide (a common anesthetic)

• Common name for H2O is water, but what would its scientific name be?

Answer: dihydrogen monoxide• What about ammonia (NH3)?

Naming Acids

• Binary acids:– Hydrogen + one other element– Name: hydro- + root of second element + -ic– Example: HCl = hydro-chlor-ic acid– What is HBr?– Hydrogen + polyatomic ion (WITHOUT oxygen) is

named the same way.– Example: HCN = hydro-cyan-ic acid

Naming Acids (continued)

• Oxyacids: – Hydrogen + oxyanion (???)– If oxyanion is -ite, then acid is –ous acid.

(EX: HNO2 = nitrous acid)

– If oxyanion is ate, then acid is –ic acid. (EX: HNO3 = Nitric acid)

• These are only ACIDS when dissolved in water!!!– HCl gas is “hydrogen chloride”.– HCl dissolved in water is “hydrochloric acid”.

Writing Formulas From Names

• Look at your FLOWCHART!!!• Compare your flowchart to Fig. 9-9, p.251.• Practice together: P.251 (27)

Assignments 1. Study Guide for Content Mastery

workbook: p.50

2. Practice Problems:a. P.249 (13-17)

b. P.250 (18-22)

3. Section Assessment: p.251 (23, 24, 26, 29)