Ionic Compounds
Guiding Question
What are the properties of ionic compounds, and how are they formed?
Forming Chemical Bonds
Read Pages 210 - 214
Complete the Section 8.1 Assesment on page 214
Intramolecular Chemical Bonding: Ionic, Covalent, and Metallic Bonding
Ionic Bonding
Types of elements involved:
Between metals and nonmetals
Givers and/or takers of electrons:
Between givers and takers
Description:
Transfer e-
Makes (+) and (-) ions that are attracted to each other.
Types of material formed:
Ceramics and glasses
Strength of bond:
Very strong
Properties produced:
Brittle, high melt temps, nonconductors as solids, don’t corrode
Covalent Bonding
Types of elements involved:
Between nonmetals
Givers and/or takers of electrons:
Between takers
Description:
Share e-
Forms discrete molecules.
Types of material formed:
Polymers AND ceramics and glasses click here to find out why
Strength of bond:
Very strong
Properties produced:
Insulators, don’t corrode
Metallic Bonding
Types of elements involved:
Between metals
Givers and/or takers of electrons:
Between givers
Description:
Valence electrons roam freely between many atoms (delocalized). Sea of electrons surrounding (+) kernels
Types of material formed:
Solid metallic elements and alloys
Strength of bond:
Relatively strong
Properties produced:
Good conductors, workable, corrode easily, generally high melt temps but variable
The Two Kinds of Covalent Bond
Network Covalent Bonds
Structure: a network of repeating lattices of covalently bonded atoms.
Properties: high melting and boiling points and are insoluble in water. The bonds between the atoms in the lattice are strong and so take a lot of energy to break
Material Formed: ceramic
Examples of Materials: SiO2 is quartz or glass, C lattice is dimond or graphite
Other Examples (liquids and gasses): these compounds are not liquids at room temperatur and pressure
Example Shown: Quartz
Molecular Covalent Bonds
Structures: consist of individual molecules.
Properties: low melting and boiling points. The covalent bonds between the atoms within the molecules are strong, but the intermolecular forces are weak, and so don’t require a lot of energy to be broken.
Material Formed: polymer
Examples of Materials: (CH2-CHCl)n is PVC, [CH2-CH(C6H5)]n is Polystyrene
Other Examples (liquids and gasses): H2O, CO2, C8H18
Examples Shown: Nylon
Interactive Self Assessment: Ionic, Covalent, and Metallic Bonding
Credit goes to Texas Gateway Online Resources for the coding on this
Directions: Match the type of bonding to the types of atoms that make up that bond.
Fun Experiments to do at Home:
Physically Breaking Intramolecular Bonds Triboluminescence
Want proof intramolecular chemical bonds are held together with charged particles? Want to check out an amazing phenomenon whose explanation is still debated by scientists, and is something you can experiment with at home? Look no further than triboluminescence. Triboluminescence is the generation of light through the breaking of chemical bonds through rubbing, ripping, scratching, breaking, or in our case crushing. The name
triboluminescence comes from the Greek tribein ("to
rub") and the Latin lumen ("light"). This optical phenomenon occurs as electrical fields are created through the separation and reunification of positive and negative charges.
It isn't just wintergreen mints that display triboluminescence. Quartz will show triboluminescence when it is rubbed together. Check it out for yourself!
If you don't want to waste the wintergreen, step into a dark room with a mirror and pop a wintergreen Life Savers in your mouth and watch for the blue flashes.
For more info see this research paper. Want to check out the full Life Saver's video click here.
Online Interactive: Ionic and Covalent Bonding Periodic Table
In this simulation, you will investigate both ionic and covalent bonding. You will have the opportunity to interact with many possible combinations of atoms and will be tasked with determining the type of bond and the number of atom needed to form each. The simulation visually differentiates between the transferring of electrons when forming an ionic compound and the sharing of electrons when forming a covalent compound so that students can have a complete understanding of each. Finally, you will become familiar with the molecular formula, as well as the naming system for each type of bond and geometric shape, when applicable.
Online Interactive: Gridlocks Bonding Types
Gridlock is a puzzle game, requiring you not just to recall the information from class,but also use your problem solving skills to unlock the grid. In this Gridlock each row, column and 2 x 2 box contains one piece of information about the three basic bonding types. Based on your understanding of significant figures, move the number tiles into the grid to solve the puzzle and unlock the grid.
The Formation and Nature of Ionic Bonds
Read Pages 215 - 220
Complete the Section 8.2 Assesment on page 220
Names and Formulas of Ionic Bonds
Read Pages 221 - 227
Complete the Section 8.3 Assesment on page 227
Online Interactive: Ionic Bonding
This interactive activity from ChemThink discusses ionic bonding—a type of chemical bond formed between two ions with opposite charges. Investigate how the transfer of electrons between atoms creates ions and how the mutual attraction of these charged particles forms ionic bonds. Also learn about trends in the periodic table of elements, and explore how the structure of an ionic compound relates to its formula.
Metallic Bonds and the Properties of Metals
Read Pages 228 - 231
Complete the Section 8.4 Assesment on page 231
Lab: Heat-Treating Steel
In this lab you will be investigating how different types of heat treatment affect different types of steel. For this, we will use bobby pins and paper clips. Bobby pins are high carbon steel (approximately 0.7%) and paper clips are low carbon steel (approximately 0.2%).
LEARNING TARGETS
-
Determine through investigation how annealing changes the properties of steel
-
Determine through investigation how quenching changes the properties of steel
-
Determine through investigation how tempering changes the properties of steel