Water is a liquid substance with different physical properties depending on its state. At room temperature, water molecules are able to move around quicker than solids, forming fewer hydrogen bonds and resulting in the formation of molecules. A single drop of water weighing 0.1g contains about 3 billion trillion molecules.
Water molecules interact through hydrogen bonding, which allows them to form fewer hydrogen bonds and take the shape of any container they are in. The particles in liquids are arranged randomly and close together, touching many of their neighbors. They cannot usually be compressed or squashed. Towels absorb liquids like water because their fibers are made of molecules that are attracted to water molecules.
As a liquid, the attractive forces between molecules weaken, allowing individual molecules to move around each other. This results in water taking the shape of any container it is in. At lower temperatures, water molecules in the liquid phase move more slowly and coalesce more easily, increasing the rate of crystal formation.
The orientation of hydrogen bonds as water changes states dictates the properties of water in its gaseous, liquid, and solid forms. In liquid water, the molecules are chaotic, jumbled, and packed densely together. As ice forms, the molecules arrange themselves in a crystal structure with a free surface in a gravitational field.
In the liquid phase, molecular forces are weaker than in a solid, and water molecules happily attract each other due to their polarity. Hydrogen bonds cause water to be exceptionally attracted to each other, making it very cohesive.
📹 Solids, liquids and gases of water molecules
An animation of the behaviour of water molecules as they are heated through the states of solid, liquid and then gas.
What causes the water molecules to behave in this manner?
The distinctive characteristics of water are ascribed to its polarity and the capacity of its molecules to establish hydrogen bonds with one another and other molecules.
How do molecules in a liquid act?
Matter is composed of small atoms or molecules, with three common states: solid, liquid, and gas. Solids are denser than liquids and gases, with particles touching with little space between them. In a solid, attractive forces keep particles together tightly enough to prevent them from moving past each other. The vibration of particles in a solid is related to their kinetic energy, and they vibrate in place.
Gas and liquid particles change shape to fit their container’s shape, while gas particles have large distances between them. In summary, matter is made up of small particles of atoms or molecules, with solids being denser than liquids and gases.
How can you justify that water is a liquid?
At room temperature (27°C), water is a liquid due to its non-fixed shape and fixed volume. It takes the shape of the container it is kept in, and the intermolecular force of attraction between water molecules is strong. The melting point of water is 0°C, below room temperature, indicating its liquid state. The boiling point of water is 100°C, above room temperature, indicating its liquid state. The intermolecular force of attraction between water molecules is also strong. Therefore, water remains in the liquid state at room temperature.
What causes water to be a liquid?
Water’s liquid nature at ambient temperatures is due to hydrogen-bonding between neighboring water molecules and the high density of molecules due to their small size. This cohesive effect is supported by van der Waals interactions and electrostatic effects, resulting in a two-state structure of high-density and low-density networks. In the liquid state, hydrogen atoms constantly exchange between water molecules due to protonation/deprotonation processes and transfer along water wires.
Both acids and bases catalyze this exchange. The average time for atoms in an H 2 O molecule to stay together is only about a millisecond, but this is often treated erroneously as a permanent structure. Water can support acid-base equilibria over an extensive range and as a solvent, it can accept protons from acids and donate protons to bases, revealing its amphoteric character, which is crucial to life.
How do water molecules react?
Hydrogen bonding represents a relatively weak interaction between a partially positively charged hydrogen atom and a more electronegative atom, such as oxygen. In this process, the positive end of one hydrogen atom associates with the negative end of another, forming a weak bond.
Why does a liquid behave as it does?
Liquid particles possess sufficient kinetic energy to overcome the attractive forces that bind them, thereby enabling their movement and flow. In a diagrammatic representation, the particles should be depicted as being in contact with one another, but distributed randomly, with the inclusion of large interstitial spaces between them, which permit the compression of the liquid. This enables the efficient flow and pouring of liquids.
How do water molecules behave in liquid water?
Water’s states are gas, liquid, and solid. Hydrogen bonds are crucial for life and are formed and broken by water molecules due to their motion due to heat. When boiling water, the higher kinetic energy causes the bonds to break completely, allowing water molecules to escape into the air as gas. Conversely, when the temperature of water drops and water freezes, water molecules form a crystalline structure maintained by hydrogen bonding, making ice less dense than liquid water. This is a phenomenon not seen in the solidification of other liquids.
Water’s lower density in its solid form is due to the orientation of hydrogen bonds as it freezes. This causes water molecules to be pushed farther apart compared to liquid water. Solidification when temperature drops also lowers kinetic energy between molecules, allowing them to pack more tightly and giving the solid a greater density than the liquid. Understanding these chemical features is essential for understanding life and the properties of water.
What is the molecule behavior of liquid?
Liquids are described using a modified version of the kinetic molecular theory of gases, which explains their higher density, greater order, lower compressibility, thermal expansion, diffusion, and shape. This model takes into account the nonzero volumes of particles and strong intermolecular attractive forces. When a flask is tilted, molecules move due to gravity, occupying openings and causing a net flow of liquid out of the container. The key takeaway is that the kinetic molecular description of liquids must consider both nonzero particle volumes and strong intermolecular attractive forces.
How do water molecules act like?
The adhesive and cohesive properties of water molecules enable them to bind together, facilitating their absorption into various surfaces.
How do molecules behave like a liquid?
Solids are characterized by their tightly packed molecular structure, which limits their ability to undergo significant molecular motion. In contrast, liquids possess a greater degree of molecular space, enabling them to exhibit greater molecular mobility.
How do liquid particles behave?
In liquids, particles move randomly and collide more frequently than in gases due to shorter distances between particles. As temperature increases, particles move faster due to gaining kinetic energy, leading to increased collision rates and diffusion rates. In solids, particles pack tightly in a neat and ordered arrangement, allowing movement but causing vibration. As temperature increases, particles gain kinetic energy and vibrate more strongly.
The attractive force in solids doesn’t need to be stronger than in liquids or gases. For example, the forces between solid helium particles are weak, while the forces between iron vapour particles are strong. When comparing different substances at the same temperature, the average kinetic energy of particles remains the same, but the attractive forces in solids are greater than those in liquids and gases. Attractive forces don’t weaken as a substance moves from solid to liquid to gas state, but the kinetic energy of particles increases, allowing them to overcome the attractive forces.
📹 How polarity makes water behave strangely – Christina Kleinberg
Water is both essential and unique. Many of its particular qualities stem from the fact that it consists of two hydrogen atoms and …
Based on my knowledge, oxygen attracts the electrons because it is more electronegative than hydrogen. Electronegativity is a measure of an atom’s ability to attract electrons in a chemical bond. Oxygen, fluorine, and nitrogen are the most electronegative elements. I believe that water’s polarity has nothing to do with the size of the oxygen atoms. Again, this is based off of my knowledge. However, the rest of the article was nicely done and informative. That is what I love about TED-Ed articles. I learn a lot from these articles. I really appreciate the time and effort these people put into making articles. Thanks!
It doesn’t explain why the molecule is polar though. To do that, you have to explain the spatial relation of orbitals, as explained by quantum mechanics. Those classical explanations about the behavior of matter are nice and easy, but ultimately we’re not offering the proper tools to really understand what’s going on.
And to add to my previous reply: not all liquids do freeze from top to bottom. Water does it exactly for the very reason stated in the article; ice is less dense and thus floats. In reality, most liquids freeze from the bottom first, as they simply dense up as they freeze. Nonpolar liquids do have surface tension as you said, but it is considerably weaker and probably doesn’t even support the weight of most insects — I couldn’t find any research material on that, though.
It’s pretty clear to me. Maybe the only part that didn’t make much sense was the explanation that H-forces made the solid state of water less dense than the liquid state. What about other liquids that also have hydrogen forces between their molecules? Are their solid states, due to them having hydrogen forces, also less dense than their liquid states?
Unequal sharing is pretty much a lack of balance or symmetry in charge as you refer to it. If a pair of atoms is shared 50/50 to 2 atoms, it’s a nonpolar & covalent bond and an unequal share, e.g., 45/55, the electron pair is slightly closer to the electronegative atom and you have a polar bond. If the electrons go all the way to the other atom, you create a big electronegative difference causing an ionic bond and in both cases you have “lack of symmetry” (not 50/50) and it is an unequal share.
Ultimately, yes, but the first half of the article spends some time discussing how atoms have valence electrons and how they form covalent bonds, and I felt like that discussion could have been better. For example, with the explanation given, it doesn’t explain why water molecule is bent, and the H and O atoms don’t line up on an axis, say like CO2.
Comune proprietà che la rendono unica e capace di sostenere la vita La polarità si riferisce alla distribuzione diseguale degli elettroni all’interno di una molecola L’ossigeno è un atomo piú grande di quello di idrogeno con più protoni nel nucleo rispetto all’idrogeno Sono in grado di attrare gli elettroni carichi negativamente nel legame. Quindi l’ossigeno può attrare più del suo quantitativo di elettroni. Mentre l’idrogeno perde l’attratività poichè ha meno protoni e elettroni. I legami interni di una singola molecola d’acqua si chiamano LEGAMI COVALENTI POLARI. COVALENTE:significa che gli elettroni sono condivisi Ma POLARE significa che questi elettroni non sono condivisi equamente. Nell’acqua l’ossigeno si comporta da negativo, e l’idrogeno da positivo. Poiché positivo e negativo si attraggono, l’ossigeno è attratto dagli atomi di idrogeno nelle vicine molecole d’acqua.
What do you mean by “laws of bonding”? Are you referring to the covalent bond itself or the intermolecular hydrogen bonds? Either way, there is no reason for them to not apply in space… They are the result of mere attraction forces. If the planets, at a much bigger scale, gravitate and are attracted towards other bodies, why wouldn’t molecules behave this way too? 🙂
Disliked. Polarity is not due to unequal sharing. Polarity refers to a lack of symmetry of charge. Like when one end is + and the other -. The reasons given for O and H having – and + charge are wrong. The reason for lakes freezing from the top down is wrong. All liquids do this. The surface tension is idea correct, but all liquids do this, even non-polar ones, so this is wrong.