University:
High School
Course:
High School Chemistry
Academic year:

2021
Views:

55

Pages:

7
Author:

Azaria Hatfield

Molecule Polarity Basic concept: Molecules which are symmetric are nonpolar molecules. Nonpolar molecules have very weak forces of attraction between them. Molecules which are asymmetric (not symmetric) 1 are polar molecules. Polar molecules have relatively strong forces of attraction between them. Examples of symmetric molecules: NON-POLAR MOLECULES: NonPolar Covalent Bonds H-H O=C=O H-C-H Always NP H₂ Molecules SYM - Determines Molecule (atoms identical) linear shape CO₂ (atoms different, but symmetric) linear shape CH₄ (tetrahedral shape) Examples of asymmetric molecules: POLAR MOLECULES: Polar Covalent Bonds SYM - Determines Molecule H-O H H₂O bent or angular shape H-N-H H NH₃ pyramidal shape H-F linear shape (atoms must be different) Ionic Bonds = ALWAYS POLAR MOLECULES NOT SYM FOR CHARGE Name: For the following compounds: Draw the electron dot structures to show the bond and atom arrangements. Name the type of bonds in each compound as (a) polar covalent (b) nonpolar covalent (c) ionic - Make sure to include the charges (d) coordinate covalent Name the type of molecule that each compound forms as (a) polar (b) nonpolar KCl Ionic [K⁺] [Cl⁻] Not Sym Polar Molecule Salt H₂ Non Polar Covalent Bond H:H SYM Non Polar Molecule CH₄ Pol Cov Bond H | H-C-H | H SYM Non Polar Molecule SiO₂ Pol Cov Bond :O::Si::O: SYM Non Polar Molecules MgO Ionic [Mg²⁺] [O²⁻] Not Sym Polar Salt K₂S Ionic [K⁺] [S²⁻] [K⁺] Not Sym Polar Salt CaBr₂ Ionic [Ca²⁺] [Br⁻] [Br⁻] Not Sym Polar Salt NH₃ Pol Cov Bond H | H-N-H | H Not Sym Polar Molecule