Honors Chemistry - Ionic Compounds

How and why do cations lose electrons and anions gain electrons? Include electron configurations.

Cations lose electrons to gain stability which results in a positive charge due to the higher number of protons than electrons.

Anions gain electrons to gain stability which results in a negative charge due to the lower number of protons than electrons.

exs:

CATION - Na: 1s²2s²2p⁶3s¹ → 1s²2s²2p⁶

ANION - Cl: 1s²2s²2p⁶3s²p⁵ → 1s²2s²2p⁶3s²p⁶

How do transition metals achieve ion formation and why do they sometimes have more than one? Give electron configurations for two oxidation states of a transition metal as an example.

Transition metals form ions by losing electrons first from the outermost s orbital and then from the inner d orbitals this provides multiple different ion formations because a variable electron loss.

Iron: [Ar}4s²3d⁶

loses 2 - Fe²⁺ ([Ar]3d⁶)

loses 3 - Fe³⁺ ([Ar]3d⁵)

Define an ionic bond and an ionic compound. Give two examples of ionic compounds.

Ionic Bond: the electrostatic attraction between oppositely charged ions.

Ionic compound: a compound form from oppositely charged ions - crystal lattice (contains ionic bond)

exs: NaCl & CaCO₃

Describe general properties of ionic compounds. Give two specific examples of these properties.

1. Crystal lattice

2. neutral → NaCl is Na⁺ and Cl^-

3. specific shaped crystals → nacl is a cube Crystal

Give a general statement about the strength of ionic bonds. Include three examples of properties of ionic compounds with your answer that are a result of bond strength.

Ionic bonds are generally very strong due to a crystal lattice repeating pattern.

exs: high melting point, high boiling point, hard but brittle

What is a crystal lattice?

Crystal lattice is a three-dimensional geometric arrangement of particles in a highly organized structure. Each negative ion is surrounded by a positive ion and the size and shape of the crystal are dependent on relative numbers of ions and their sizes.

Which compound has a higher lattice energy and why? → NaCl or RbCl

NaCl because Na is smaller than Rb and holds tighter bonds.

Give the four rules for writing a formula unit for an ionic compound.

1. cation then anion

2. balances charges for neutrality

3. use subscripts to show ratios

4. use parentheses for polyatomic ions

Summarize the five rules for naming ionic compounds.

1. cation than anion

2. monoatomic cations write the element name

3. monoatomic anions write the root of element plus the suffix -ide

4. multiple oxidation states are represented by Roman numerals

5. polyatomic ions write cation and then polyatomic ion

Describe a metallic bond and include a definition of the electron sea model and delocalized electrons within your answer.

A metallic bond is the strong electrostatic attraction between a lattice of positive metal ions and is surrounding “sea” of mobile delocalized electrons.

Identify five properties of metals that are a direct result of metallic bonding.

1. malleable

2. ductile

3. boiling points are high as well as melting points

4. mobile electrons around cations

5. conductivity

Define Alloys and categorize them into two basic groups. Include two examples each.

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

Substantial: Brass, Bronze

Interstitial: Cast Iron, Steel

How does energy and stability relate to ion formation and bond formation? In other words why the atoms bond?

The process of forming bonds or ions releases energy making the resulting compound more stable than the original atom. The reduction of potential energy is released as heat, and bond formation is exothermic.

How are ionic and metallic bonds similar on how are they different?

Similar: result in crystal lattice structures, high boiling and melting points

Different: In ionic crystal lattice is cations and anions while in metal crystal lattice is cations and delocalized electrons, metals are malleable ductile and conductive and ionic is none because electrons don't move