Model

Students work in groups to construct 3D molecular models. and connect the models by rubber bands representing an intermolecular force. Students a. identify the partial positive charge atoms and the partial negative charge atoms in each model that are involved in the IMF, b. calculate the difference in electronegativity between the opposite charged atoms, c. select the appropriate rubber band width to correlate with the strength of the IMF between models, d. correlate the strength of the IMF to a physical property of the liquid state of the compound - boiling point, vapor pressure, and Heat of Vaporization.

VSEPR Ball and Stick Molecular Models

VSEPR Balloons of the five basic shapes of molecules,

Students visualize and represent molecules in 3-Dimensions. High quality plastic individual model kits for VSEPR configurations are used to enable students to build molecular models. Using an active learning approacah, given a molecular formula, students draw the Lewis Structure, Identify the total regions of electron domains around the central atom, build the model of the molecule, draw a 3D representation of the molecule, identify the molecular shape, identify the bond angles, and classify the molecule as polar or non-polar.

Activity Parts I and II: Students work in pairs to model intermolecular forces by labeling and manipulating plastic arrows and rectangles: General structures, IMFs in pure substances, IMFs in a mixture. Activity Part III: Students work in pairs by labeling and manipulating plastic arrows and rectangles with specific structures, or real compounds: KBr, ethane, ethanol, dimethy ether; identify IMFs in pure substances and IMFs in a mixture, place the arrow with the IMF to connect opposite charges.

A drop of acetone evaporates faster than ethanol, the ethanol evaporates faster than a drop of water.

Large-scale molecular model kit depicting sp, sp2, sp3 hybridization of carbon, sigma and pi bonding orbitals.

A beach ball and a wooden box show how big a mole of gas is.