01 What is Water?
The most important molecule on Earth. Its bent shape and polarity give it unique properties: high surface tension, capillary action, excellent solvent capability, and anomalous density (ice floats on liquid water).
02 Why It Matters
Water's polarity makes it the universal solvent - it dissolves salts, sugars, proteins, and gases. Its high specific heat capacity buffers temperature on Earth. Hydrogen bonding gives ice a lower density than liquid water, so it floats - preventing lakes from freezing solid.
03 Structure and Bonding
Shape: Bent (104.5ยฐ)
Bonds: 2 polar O-H covalent bonds
Polarity: Polar - The asymmetry of the molecule means bond dipoles don't cancel, giving the molecule a net dipole moment. This affects its solubility, boiling point, and interactions with other molecules.
A single water molecule can form up to 4 hydrogen bonds simultaneously - 2 as donor, 2 as acceptor.