Exploring 2 Types of Bonds

1. Exploring 2 Types of Bonds Science 10 Chemistry Unit

2. There are 2 types of bonds: • Ionic bonds • Covalent (or molecular) bonds

3. Ionic Bonds • Ionic bonds are formed when one or more electrons are transferred from one atom to another atom. • This produces positively and negatively charged particles called ions.

4. The forces of attraction that bind oppositely charged ions together are called ionic bonds. • Ionic bonds generally occur between metals and nonmetals (cations and anions). • Anions and cations are held together in an ionic bond due to electrostaticforces --- oppositely charged “force fields” resulting from the oppositely charged ions.

5. Examples: • NaCl • Fe2O3 • BaF2

6. Covalent Bonding: • Involves the “sharing” of electrons. • It involves the bonds formed between a non-metal and a non-metal (or metalloid).

7. Important: • Since these bonding non-metals (or metalloids) wish to gain electrons to become like a noble gas, and they can’t gain electrons from each other at the same time, they must share their electrons so they can both become like a noble gas. • These compounds or molecules that are formed are neutral…they have no charge.

8. Examples • H2O (water) • CO2 (carbon dioxide) • O2 (oxygen)

9. Nomenclature: • Different classes of compounds have different rules for naming.  • Before naming a compound, it is important to check which class it belongs to so that you will use the appropriate set of rules.

10. Rules for Naming Binary Molecular Compounds • To use this set of rules, the compound must be a molecular or covalent compound.  • In other words, it must be a non-metal + a non-metal (or metalloid) compound

11. Rules: • Name the first element as the name you see on your periodic table. • Name the second element as you see it in your “Periodic Table of Ions”…the 2nd element always ends in “-ide” • Use numerical prefixes to show how many of each atom is present in the molecule. • Mono- is frequently or often, omitted.  • Write these on the “file cards”then place them in your plastic sheath.

13. Sulphur trioxide Dinitrogen monosulfide Naming Binary Molecular Compounds Write the names of the following covalent compounds: • SO3 _______________________________________ • N2S _______________________________________ • PH3 _______________________________________ • BF3 _______________________________________ • P2Br4 ______________________________________ • CO ________________________________________ • SiO2 _______________________________________ • SF6 _______________________________________ • NH3 _______________________________________ • NO2 ________________________________________ Phosphorous trihydride Boron trifluoride Diphosphorous tetrabromide Carbon monoxide silicon dioxide Sulphur hexafluoride Nitrogen trihydride or Ammonia nitrogen dioxide

14. NCl3 BC N2O3 Formula Writing of Binary Molecular Compounds • nitrogen trichloride ________________________ • boron monocarbide __________________________ • dinitrogen trioxide ________________________ • phosphorus pentafluoride __________________ • methane ______________________________ • sulfur dibromide _________________________ • diboron tetrahydride ______________________ • oxygen difluoride _________________________ • carbon disulfide __________________________ PF5 CH4 SBr2 B2H4 OF2 CS2