Water

Need to know

What you need to know

• Water is a polar molecule due to unequal electron sharing, leading to δ+ hydrogen and δ- oxygen atoms.
• Hydrogen bonds form between water molecules, underpinning all of its unique properties.
• High Specific Heat Capacity: Water resists temperature changes, providing a stable internal environment for cells and aquatic habitats.
• High Latent Heat of Vaporisation: Evaporation of water (e.g., sweat) provides a powerful cooling effect.
• Excellent Solvent: Water's polarity allows it to dissolve and transport polar solutes like glucose, ions, and waste products.
• Cohesion & Adhesion: These forces are responsible for surface tension and the movement of water up plant xylem (transpiration stream).
• Density Anomaly: Ice is less dense than liquid water, so it floats, insulating aquatic environments in winter.
• Metabolite: Water is a reactant in hydrolysis reactions (breaking down molecules) and a product in condensation reactions (building molecules).

Explanation

Water

1. Water is a polar molecule due to unequal electron sharing, leading to δ+ hydrogen and δ- oxygen atoms.
2. Hydrogen bonds form between water molecules, underpinning all of its unique properties.
3. High Specific Heat Capacity: Water resists temperature changes, providing a stable internal environment for cells and aquatic habitats.
4. High Latent Heat of Vaporisation: Evaporation of water (e.g., sweat) provides a powerful cooling effect.