A bent little molecule with a split personality — and the reason life works the way it does.
Oxygen is more electronegative than hydrogen, so it pulls the shared electrons closer. The O end goes slightly negative (δ−), the H ends slightly positive (δ+).
The molecule is bent, not linear, so the charges don't cancel. Water is a permanent dipole — one molecule with a + side and a − side.
The δ+ H of one molecule is attracted to the δ− O of another, forming a hydrogen bond. Weak singly, but vast numbers together explain almost everything water does.
Tap a part to see why each one matters.
Tap a part to see why it matters.
Each molecule is a dipole: a green δ− oxygen, two pink δ+ hydrogens. Watch how opposite charges pull molecules into line — a blue dashed link appears wherever a δ+ H meets a δ− O. That link is a hydrogen bond. Add heat and watch them break.
At low energy, molecules orient so δ+ hydrogens face δ− oxygens, locking into a lattice of hydrogen bonds — that order is why ice floats and why water resists temperature change. Add energy and the molecules jostle free: bonds break, the count drops, and water moves toward boiling.
Water's physical properties — buoyancy, viscosity, thermal conductivity and specific heat — shape the animals that live in it. Tap an application point on the ringed seal or the black-throated loon.
Tap a numbered point to see which property of water it answers to.
Tap a concept to light up how it connects.
Everything radiates from one fact: water is polar. Tap a concept to trace how polarity becomes every property water is famous for.
Tap any concept to trace its connections · tap the background to reset
Drag each term into the gap it belongs in. Two terms are traps.
Single best answer, Paper 1 style. Pick one — you'll see why.