Unit 4 Test Review

Identify the following as covalent or ionic.

1. water (H2O)

2. salt (NaCl)3. iron (II) sulfide

(FeS)4. calcium

bromide (CaBr2)

1. covalent2. ionic3. ionic

4. ionic

Identify the following as covalent or ionic.

1.CS2

2.BaI2

3.N2O4

4. PCl3

1.covalent2.ionic3.covalent4.covalent

Identify the following as covalent or ionic.

1. compound is a gas at room temperature

2. compound, when melted, conducts an electric current

3. compound is composed of a metal and a nonmetal

4. compound is composed of a nonmetal and a nonmetal

1. covalent

2. ionic

3. ionic

4. covalent

What is a polyatomic ion?

• An ion that contains more than 1 element

What is meant by binary ionic?

• 2 elements (metal and nonmetal) joined by ionic bonds

What is meant by binary molecular?

• 2 elements (both nonmetals) joined by covalent bonds

What is meant by ternary ionic?

• 3 elements (metal and nonmetals) joined by ionic bonds

What part of the atom is involved in chemical

reactions?

•Valence electrons

Why do atoms share electrons?

• To gain the electron configuration of a noble gas

Which intermolecular attractive force is the strongest?

• Hydrogen bonds

Why is carbon special?

– it has four electrons in its outermost energy level

– it readily bonds with other carbon atoms

• it can form single, double, or triple bonds with other atoms

What is the Octet Rule?

• in chemical compounds, atoms tend to have the electron configuration of a noble gas

What is the electron configuration of the sulfide ion

(S-2)?

• 1s22s22p63s23p6

A compound that ends in -ate or -ite contains ____.

•A polyatomic ion

How many valence electrons are transferred from the aluminum

atom to oxygen in the formation of the compound aluminum oxide?

•3

Why are metal good electrical conductors?

•They have mobile electrons

Which elements can form diatomic molecules joined by a single covalent bond?

• halogens and hydrogen

Which elements can form diatomic molecules joined by double covalent bonds?

• oxygen

Which elements can form diatomic molecules joined by triple covalent bonds?

• nitrogen

What is VESPR Theory?

• molecules adjust their shapes to keep valence electrons as far apart as possible

What is a polar molecule?

•A molecule that has partial positive and negative charges

Which of the following covalent bonds is the most polar?

• a. H—F

• b. H—C

• c. H—H

• d. H—N

What is the charge on the cation in the ionic compound

magnesium chloride?

•+2

What is the net charge of the ionic compound potassium

fluoride?

0

What is the formula unit of calcium nitride?

•Ca3N2

What is the formula for potassium sulfate

K2SO4

What is the formula unit for sodium sulfide?

Na2S

What is the name of the following compound?

NaClO2

•Sodium chlorite

Are the following pairs of elements likely to form ionic

or covalent compounds?

• phosphorus and sulfur

• magnesium and oxygen

• aluminum and chlorine

• covalent

• ionic

• ionic

What are some properties of ionic compounds?

• High melting points• Metal and nonmetal• Conducts electricity in solution• solid

What is a cation?

• An ion with a positive charge due to loss of electrons

• The metal part of an ionic compound

What is an anion?

• An ion with a negative charge due to gain of electrons

• The nonmetal part of an ionic compound

Will group 6A elements gain or lose electrons when forming

ions?

How many electrons will be gained or lost?

•gain•2

What is the purpose of a Roman numeral following the name

of an element?

• To indicate the presence of a transition metal that can have more than one common ionic charge.

What ion will sulfur form?

•S -2

•sulfide

What is the formula for iron (III) oxide?

•Fe2O3

What is the formula for phosphorus tetrachloride?

•PCl4

What is the formula for trisulfur dioxide?

•S3O2

Reactions between atoms involve which part of the

atom?

•Valence electrons

What is the name of the following compound?

CrF3

•Chromium (III) fluoride