General Chemistry 2 Lesson 1.4

Importance of Water

• Water is essential for all life forms on Earth; researchers seek traces on other planets to find potential life.
• Used by humans for drinking, cooking, cleaning, and creating substances.
• Presence of liquid water on a planet increases the likelihood of life similar to Earth.

Composition of Water on Earth

• Water constitutes a significant portion of the biosphere: 95% saltwater and 5% freshwater.
• Exists in various forms: ice, glaciers, underground lakes, soil, atmosphere, and rivers.
• The human body is composed of approximately 70% water.

Unique Properties of Water

• Unique properties arise from strong intermolecular hydrogen bonds.
• Properties include high specific heat, high surface tension, and solvent abilities vital for biological processes.

Molecular Structure of Water

• Represents with chemical formula H2O; consists of two hydrogen atoms bonded to a central oxygen atom.
• The electron domain geometry around the oxygen atom is tetrahedral due to four electron domains but features two lone pairs.

Molecular Geometry

• Presence of two lone pairs results in a bent molecular geometry.
• Oxygen's higher electronegativity creates a dipole moment, making the molecule polar with partial charges between O and H atoms.

Intermolecular Forces

• Water molecules undergo hydrogen bonding due to their polarity.
• The neutral charge of water does not result in full charges but in partial positive (H) and negative (O) charges, leading to significant interactions between molecules.

Importance of Water

• Water is essential for all life forms on Earth; researchers seek traces on other planets to find potential life.
• Used by humans for drinking, cooking, cleaning, and creating substances.
• Presence of liquid water on a planet increases the likelihood of life similar to Earth.

Composition of Water on Earth

• Water constitutes a significant portion of the biosphere: 95% saltwater and 5% freshwater.
• Exists in various forms: ice, glaciers, underground lakes, soil, atmosphere, and rivers.
• The human body is composed of approximately 70% water.

Unique Properties of Water

• Unique properties arise from strong intermolecular hydrogen bonds.
• Properties include high specific heat, high surface tension, and solvent abilities vital for biological processes.

Molecular Structure of Water

• Represents with chemical formula H2O; consists of two hydrogen atoms bonded to a central oxygen atom.
• The electron domain geometry around the oxygen atom is tetrahedral due to four electron domains but features two lone pairs.

Molecular Geometry

• Presence of two lone pairs results in a bent molecular geometry.
• Oxygen's higher electronegativity creates a dipole moment, making the molecule polar with partial charges between O and H atoms.

Intermolecular Forces

• Water molecules undergo hydrogen bonding due to their polarity.
• The neutral charge of water does not result in full charges but in partial positive (H) and negative (O) charges, leading to significant interactions between molecules.