18 Questions
What is the bond angle for a molecule with a linear shape?
180°
Which molecule has a trigonal planar shape?
BF3
What is the bond angle in a molecule with a tetrahedral shape?
109.5°
Which molecule has a trigonal pyramidal shape?
NH3
How many bond angles does a molecule with an octahedral shape have?
90°
Which type of bond is formed when two atoms share electrons equally?
Non-polar covalent bond
What does the VSEPR theory help predict in chemistry?
Molecular shapes
In the context of chemistry, what is the main purpose of completing a 3D drawing of a molecule?
To visualize its shape and structure
Which aspect of a molecule is determined by its bond angles?
Hybridization
What property of a molecule is defined by whether it is polar or non-polar?
Solubility
Which theory can be used to predict the 3D shapes of molecules resulting from hybridization?
VBT (Valence Bond Theory)
How does understanding the polarity of a solid influence its properties?
It affects its crystal lattice structure
What is responsible for the formation of London dispersion forces?
Instantaneous dipoles induced by moving electrons
Which intermolecular force has the greatest strength?
Hydrogen bonding
What property of a substance increases as the atoms in its molecule get larger?
Polarizability
Why do water droplets bead?
Because of hydrogen bonding
What is the primary intermolecular force responsible for surface tension?
Hydrogen bonding
Which type of composite material consists of two or more materials that remain separate and distinct from each other?
Heterogeneous composite
Study Notes
Electron Pair Repulsion
- Bonded and lone pair electrons move apart to lessen repulsive forces between them
- This leads to specific molecular shapes
Molecular Shapes
- Linear: 180° bond angle, ex. BeCl2
- Trigonal Planar: 120° bond angles, ex. BF3
- Tetrahedral: 109.5° bond angles, ex. CH4
- Trigonal Bipyramidal: bond angles of 90° and 120°, ex. PCl5
- Octahedral: bond angles of 90°, ex. SF6
- Trigonal Pyramidal: bond angles of 107°, ex. NH3
- Bent: bond angles 104.5°, ex. H2O
VSEPR Theory
- Predicts the arrangement of electrons around each atom individually
- Then, combines these arrangements to predict molecular shape
Multiple Central Atoms
- Predict the arrangement of electrons around each atom individually
- Then, combine these arrangements to predict molecular shape
Double and Triple Bonds
- Shorter and stronger than single bonds
- Behave similarly in regards to 3-dimensional shape of the molecule
Electronegativity and Bond Polarity
- Two types of covalent bonds: non-polar (equal sharing of electrons) and polar (unequal sharing of electrons)
- Electronegativity is the ability of an atom to attract electrons in a covalent bond
Intermolecular Forces
- London Dispersion Forces: weak, momentary forces between non-polar molecules
- Dipole-Dipole Forces: between polar molecules
- Hydrogen Bonding: strongest intermolecular force
- Intermolecular forces affect physical properties, such as melting/boiling point, viscosity, solubility, and surface tension
Learn about molecular geometry through VSEPR theory, which explains how bonded and lone pair electrons arrange themselves around a central atom to minimize repulsive forces. Explore different molecular shapes such as linear, trigonal planar, tetrahedral, trigonal bipyramidal, and octahedral. Understand concepts like bond angles and the use of wedge and dash notation.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
