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.