8 Questions
What is the primary factor that determines the polarity of a molecule?
Electronegativity difference between atoms in a bond
Which type of intermolecular force is responsible for the strong attraction between a hydrogen atom bonded to fluorine, oxygen, or nitrogen and a lone pair of electrons?
Hydrogen bonding
Which of the following molecules is non-polar?
Carbon dioxide (CO2)
What is the general trend for solubility of ionic compounds in water based on the solubility rules?
Most ionic compounds are soluble in water
Which of the following compounds is expected to be insoluble in water according to the solubility rules?
Silver nitrate (AgNO3)
What is the primary factor that determines the strength of intermolecular forces?
Polarity of the molecule
Which type of intermolecular force is responsible for the attraction between non-polar molecules?
London dispersion force
What is the effect of increasing the strength of intermolecular forces on the boiling point of a substance?
It increases the boiling point
Study Notes
Polarity
- Molecules can be polar or non-polar, affecting solubility
- Polarity depends on:
- Electronegativity difference between atoms in a bond
- Molecular shape and symmetry
- Polar molecules have a partial positive (δ+) and partial negative (δ-) charge
- Examples of polar molecules: water (H2O), ethanol (C2H5OH)
Intermolecular Forces
- Weak forces between molecules that affect solubility
- Types of intermolecular forces:
- Hydrogen bonding: strong attraction between H atom bonded to F, O, or N and a lone pair of electrons
- Dipole-dipole forces: attraction between polar molecules
- London dispersion forces: weak attraction between non-polar molecules
- Strength of intermolecular forces affects solubility and boiling point
Solubility Rules
- General rules for predicting solubility of ionic compounds in water
-
Soluble:
- Compounds containing alkali metals (Group 1) or ammonium (NH4+)
- Nitrates (NO3-), acetates (CH3COO-), and chlorates (ClO3-)
- Alkylammonium ions (e.g., NH4+, RNH3+)
-
Insoluble:
- Compounds containing silver (Ag+), lead (Pb2+), or mercury (Hg2+)
- Carbonates (CO32-), phosphates (PO43-), and sulfides (S2-)
- Hydroxides (OH-) except for alkali metals and barium (Ba2+)
- Exceptions: Some compounds may not follow these rules due to specific chemical properties
Polarity
- Molecules can be polar or non-polar, depending on the electronegativity difference between atoms in a bond and molecular shape and symmetry
- Polar molecules have a partial positive (δ+) and partial negative (δ-) charge due to unequal sharing of electrons
- Examples of polar molecules include water (H2O) and ethanol (C2H5OH)
Intermolecular Forces
- Hydrogen bonding is a strong attraction between H atom bonded to F, O, or N and a lone pair of electrons
- Dipole-dipole forces are the attraction between polar molecules
- London dispersion forces are the weak attraction between non-polar molecules
- The strength of intermolecular forces affects solubility and boiling point
Solubility Rules
- Ionic compounds containing alkali metals (Group 1) or ammonium (NH4+) are generally soluble
- Nitrates (NO3-), acetates (CH3COO-), and chlorates (ClO3-) are also soluble
- Alkylammonium ions (e.g., NH4+, RNH3+) are soluble
- Compounds containing silver (Ag+), lead (Pb2+), or mercury (Hg2+) are generally insoluble
- Carbonates (CO32-), phosphates (PO43-), and sulfides (S2-) are insoluble
- Hydroxides (OH-) are insoluble except for alkali metals and barium (Ba2+)
- Exceptions exist due to specific chemical properties
Learn about the concept of polarity in molecules, its effects on solubility, and the different types of intermolecular forces that exist between molecules.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
