Chemistry Ch 7

Alloy

An alloy is a mixture of elements that has metallic properties.

Multivalent metals exceptions and charges

Zinc: Zn2+ Silver: Ag+ Cadmium: Cd2+ Tin: Sn2+, Sn4+ Lead: Pb2+, Pb4+

metal ions in the representative elements are called

by there name

The properties of alloys

differ from the elements they contain.

Reactions that release energy are

exothermic.

Mobile electrons around cations make metals

good conductors of electricity and heat.

Ionic compounds The repeating pattern of particle packing in an ionic compound is called an _____

ionic crystal

Never change subscripts of polyatomic ions, instead...

place in parentheses and write the appropriate subscript outside the parentheses.

Other relatively stable electron arrangements are referred to as ______________

pseudo-noble gas configurations.

Ionic compounds Positive and negative ions exist in a ______ determined by the ...

ratio ...number of electrons transferred from the metal atom to the non- metal atom.

pseudo-noble gas configurations

relatively stable electron arrangements fake for ions

multivalent metals ions are called

there name and a roman numeral with the charge

________________ are formed when small holes in a metallic crystal are filled with smaller atoms.

Interstitial alloys

____________________________________ depend on the strength of the attraction. (Ionic Compounds)

Melting point, boiling point, and hardness

__________are not ionic but share several properties with ionic compounds.

Metals

Monoatomic Ion

Monatomic ions are one-atom ions.

Oxidation number

Oxidation number, or oxidation state, is the charge of a monatomic ion.

Polyatomic ion

Polyatomic ions are ions made up of more than one atom.

The smaller the ion, the greater the ________

attraction.

When writing names and formulas for ionic compounds, the _________appears first followed by the ____________.

cation anion

The value of lattice energy is also affected by the ______________

charge of the ion.

Make a compound neutral when you have positive and negative ions.

cross multiply method

Ionic Compounds The strong attractions among the positive and negative ions result in the formation of the ________

crystal lattice.

Some nonmetals can gain or lose __________

electrons to complete an octet.

Reactions that absorb energy are

endothermic.

Boiling points are much more extreme than melting points because of the

energy required to separate atoms from the groups of cations and electrons.

Nonmetal ions ____________the number of electrons required to fill an octet.

gain

Properties of ionic compounds In a solid,

ions are locked into position and electrons cannot flow freely—solid ions are poor conductors of electricity.

crystal lattice

is the three-dimensional geometric arrangement of particles, and is responsible for the structure of many minerals.

metals are reactive because they...

lose valence electrons easily

Metals are ___________because they can be hammered into sheets. Metals are ___________because they can be drawn into wires.

malleable ductile

Smaller ions form compounds with

more closely spaced ionic charges, and require more energy to separate.

Electrostatic force of attraction is inversely related to the distance between the ____________

opposite charges.

An __________is a polyatomic ion composed of an element (usually a non- metal), bonded to one or more oxygen atoms.

oxyanion

Melting point, boiling point, and hardness depend on the

strength of the attraction. higher melting and boiling point and hardness show stronger attracction

Metallic bonding involves

the metal ions in a "sea of electrons"

• Within the crowded lattice,

the outer energy levels of metal atoms overlap.

Show that column (group) of the element effects its oxidation number.

the oxidation number is the charge which atoms becomes ions through gaining or losing electrons which translates into charge gain electrons become negative lose electrons become positive

Lattice energy is directly related to

the size of the ions that are bonded.

nonmetal ions are called

there name but ending in -ide

Metals also form lattices in the solid state,

where 8 to 12 other atoms closely surround each metal atom.

Metallic bond

• A metallic bond is the attraction of a metallic cation for delocalized electrons.

Binary compound

• Binary ionic compounds contain only two different elements—a metallic cation and a nonmetallic anion.

ionic compounds.

• Compounds that contain ionic bonds are called ionic compounds.

Chemical Bond

A chemical bond is the force that holds two atoms together. • Chemical bonds form by the attraction between the positive nucleus of one atom and the negative electrons of another atom. Atom's try to form the octet—the stable arrangement of eight valence electrons in the outer energy level—by gaining or losing valence electrons.

Formula unit

A formula unit represents the simplest ratio of the ions involved.

Cation

A positively charged ion is called a cation. This figure illustrates how sodium loses one valence electron to become a sodium cation.

How do we get the charges to balance?

Al2O3

Anion

An anion is a negatively charged ion. • The figure shown here illustrates chlorine gaining an electron to become a chlorine ion.

electrolyte

An ion in aqueous solution that conducts electricity is an electrolyte.

Transition metals commonly form ________ ions, but can form ________________

2+ or 3+ greater than 3+ ions.

What is charge on oxygen when it is an ion (oxide)?

2-

What is charge on aluminum when it is an ion?

3+

Chemical nomenclature is a systematic way of naming compounds.

- Name the cation followed by the anion. - For monatomic, cations use the element name. - For monatomic anions, use the root element name and the suffix -ide. - To distinguish between different oxidation states of the same element, the oxidation state is written in parentheses after the name of the cation. - When the compound contains a polyatomic ion, name the cation followed by the name of the polyatomic ion.

The name of metals with two or more positive ions (cations) use a ___________ to identify ionic charge.

Roman numeral

Explain that lattice energy is affected by ion size and charge

Smaller ions form compounds with more closely spaced ionic charges, and require more energy to separate. • Electrostatic force of attraction is inversely related to the distance between the opposite charges. • The smaller the ion, the greater the attraction, more energy to separate. As we increase (by # not +/-) the ion charge variable, lattice energy increases. Compared to +1 or -1 ions, +2 or -2 ions will release more lattice energy.

________________ are formed when some atoms in the original metallic solid are replaced by other metals of similar atomic structure.

Substitutional alloys

Electron sea model

The electron sea model proposes that all metal atoms in a metallic solid contribute their valence electrons to form a "sea" of electrons.

Delocalized electrons

The electrons are free to move around and are referred to as delocalized electrons, forming a metallic cation.

Ionic bond

The electrostatic force that holds oppositely charged particles together in an ionic compound is called an ionic bond.

lattice energy

The energy required to separate 1 mol of ions in an ionic compound is referred to as the lattice energy.

Ionic Compound formula rules

The symbol for the cation is always written first, followed by the symbol of the anion. • Subscripts represent the number of ions of each element in an ionic compound. • The total charge must equal zero in an ionic compound.

Multivalent Metal

a metal element that can form two or more types of ions with different charges Most transition metals and Group 4A(14) metals Form 2 or more positive ions. Zn2+, Ag+, and Cd2+ form only one ion.

As the number of delocalized electrons increases, so does .

hardness and strength

Properties of ionic compounds Liquid ions or ions in aqueous (a solution in which the solvent is water. [aq]) solution have

have electrons that are free to move, so they conduct electricity easily.