Question

In liquid water, the particles (molecules) are similar in that they are all constantly moving and can slide past each other, which allows the liquid to flow. A key difference is that, unlike in a gas, the water molecules are still close together and held by hydrogen bonds, giving the liquid a definite volume.

Answer 1

That description is correct. A bit more detail:

- In a liquid the molecules are close together but not fixed in place. Each molecule has enough kinetic energy to move and slide past its neighbors, so the liquid can flow and take the shape of its container.

- Unlike in a gas, the molecules in a liquid remain close because of appreciable intermolecular attractions. In water those attractions are hydrogen bonds — relatively strong, directional interactions between the hydrogen on one molecule and the oxygen on another. The hydrogen bonds hold molecules near one another, so the liquid has a definite volume (it doesn’t expand to fill all available space the way a gas does).

- The hydrogen-bond network in liquid water is dynamic: individual H‑bonds form and break on picosecond timescales, which allows flow while maintaining cohesion. These bonds also give water its high boiling point, surface tension, heat capacity, and relatively low compressibility compared with gases.

- For contrast: solids have molecules in fixed positions (definite shape and volume) because bonding/forces lock them into a lattice; gases have molecules far apart with negligible attractions, so they fill their container and are highly compressible.

So your statement captures the essential point: mobility like a gas (flow) combined with close packing and intermolecular bonding (definite volume) — hydrogen bonding is the key difference for water.