1 / 17

Covalent Bonding

Covalent Bonding. The Sharing of electrons to complete an octet. Between Non metals only Electronegativity difference less than or equal to 1.7 Molecule is the basic unit. T ypes of Covalent Bonds. Polar Covalent Electronegativity difference between 0.3 and 1.7

raya-berg
Download Presentation

Covalent Bonding

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Covalent Bonding • The Sharing of electrons to complete an octet. • Between Non metals only • Electronegativity difference less than or equal to 1.7 • Molecule is the basic unit

  2. Types of Covalent Bonds • Polar Covalent Electronegativity difference between 0.3 and 1.7 Examples: HCl, H2O, NH3 • Non Polar Covalent Electronegativity difference between 0.3 and 0.00. Examples: H2, N2, O2, F2

  3. Formation of Covalent Bond • As two non-metallic atoms approach each other, two forces become important. 1. Force of Attraction 2. Force of Repulsion • As the atoms move closer together the attraction becomes greater until maximum attraction is reached, this is when the attractive force balances the repulsive force.

  4. Sharing of electrons Covalent Bonds can share electrons to form: 1. Single Bonds- sharing of ONE pair of electrons 1 sigmabond 2. Double Bonds- sharing of TWO pairs of electrons 1 sigma and 1 pi 3. Triple Bonds- sharing of THREE pairs of electrons 1 sigma and 2 pi

  5. Strength of Bonds • Single- held together by one pair and therefore the WEAKEST • Double- held together by two pair of electrons, stronger than single • Triple- held together by three pair and therefore the STRONGEST

  6. FACTORS THAT DETERMINE BOND STRENGTH • Bond Length- Shorter the distance, the stronger the bond as in TRIPLE BONDS. • Longer distance equals weaker bond (again think of a magnet, Closer = stronger attraction) The stronger the bond, the HIGHER the melting and boiling points of the substance, the harder it is , the more dense it is, and the more stable the molecule

  7. Shapes of Covalent Bonds • The number of bonds formed determines the shape of the molecule AND • The physical and chemical properties of that substance (molecular geometry)

  8. Shapes you are required to know • Linear, CO2 • Bent, H2O • Trigonal Planar, BH3 • Tetrahedral, CH4

  9. Prefixes Number of atomsPrefix 1 mono- 2 di- 3 tri- 4 tetra- 5 penta- 6 hexa- 7 hepta- 8 octa- 9 nona- 10 deca-

  10. Naming Molecular Compounds • Naming Binary Molecular Compounds The first element (cation) in the formula is always named first using the entire first name. NEVER CHANGE THE NAME OF THE CATION! • The second element (anion) in the formula is named using the root of the second element and adding the suffix -ide. • Prefixes are used to indicate the number of each type of atom present in the compound.

  11. Let’s Practice • Name each of the binary compounds in the Practice Problems on page 249. • CCl4 • As2O3 • CO • SO2 • NF3

  12. ACIDS An acid is a molecule with one or more H+ ions attached to an anion. There are 2 basic classifications of naming acids. 1. Binary –containing 2 elements only 2. Oxy acids – containing 3 elements-- hydrogen, oxygen and 3rd element (non-metal)

  13. RULES FOR NAMING ACIDS • If it is a Binary acid (only 2 elements), hydrogen and one other element, you use the prefix HYDRO and the root word of the second element followed by the suffix --ic. • Examples:HCl HBr HF H2S

  14. ANSWERS • Hydrochloric • Hydrobromic • Hydrofluoric • Hydrosulfuric

  15. RULES FOR NAMING “OXY” ACIDS • Named by the polyatomic ion in the formula • If the anion ending is “ATE”, replace “ate” with “IC” or “RIC”. EX: H2SO4 contains SO4 sulfate anion = sulfuric acid H3PO4 contains the PO4 anion= phosphoric “If I ate an acid it would make me sick.”

  16. If the anion ends in “ITE”, replace “ite” with “OUS” ending. EX: H2SO3 contains sulfite anion = sulfurOUS HNO2 contains the nitrite anion = nitrOUS H3PO3 contains the phosphite anion = phosphorOUS “Dynamite is dangerous”.

  17. AND NOW YOU KNOW HOW TO NAME MOLECULAR COMPOUNDS & ACIDS Remember: the basic unit of covalent compounds is called a MOLECULE.

More Related