What do particles in a solid do

The simplest way to determine if something is a liquid is to ask this question: If I try and move it from one container to another i. If you have a glass of water and pour it into another glass, it clearly conforms — it takes on the shape of the glass. If you spill the water, it will go everywhere. In most liquids, the particles are less densely packed, giving them the ability to move around and slide past each other. While a liquid is easier to compress than a solid, it is still quite difficult — imagine trying to compress water in a confined container!

Water is an example of a liquid, and so are milk, juice and lemonade. Find out more about water by looking at our wide range of resources under the water topic.

The atoms and molecules in gases are much more spread out than in solids or liquids. They vibrate and move freely at high speeds. A gas will fill any container, but if the container is not sealed, the gas will escape. Gas can be compressed much more easily than a liquid or solid. Think about a diving tank — L of gas is compressed into a 3 L cylinder. Right now, you are breathing in air — a mixture of gases containing many elements such as oxygen and nitrogen.

Water vapour is the gaseous form or state of water. They may be simple binary salts like sodium chloride NaCl , or table salt, where one atom of a metallic element sodium is bonded to one atom of a nonmetallic element chlorine.

They may also be composed of polyatomic ions such as NH 4 NO 3 ammonium nitrate. Polyatomic ions are groups of atoms that share electrons called covalent bonding and function in a compound as if they constituted a single charged ion. Molecular solids are composed of covalently bonded molecules attracted to each other by electrostatic forces called van der Waals forces, according to the HyperPhysics website. Because covalent bonding involves sharing electrons rather than outright transfer of those particles, the shared electrons may spend more time in the electron cloud of the larger atom, causing weak or shifting polarity.

This electrostatic attraction between the two poles dipoles is much weaker than ionic or covalent bonding, so molecular solids tend to be softer than ionic crystals and have lower melting points many will melt at less then C, or F.

Most molecular solids are nonpolar. These nonpolar molecular solids will not dissolve in water, but will dissolve in a nonpolar solvent, such as benzene and octane. Polar molecular solids, such as sugar, dissolve easily in water. Molecular solids are nonconductive. Examples of molecular solids include ice, sugar, halogens like solid chlorine Cl 2 , and compounds consisting of a halogen and hydrogen such as hydrogen chloride HCl.

Fullerene "buckyballs" are also molecular solids. In a network solid, there are no individual molecules. The atoms are covalently bonded in a continuous network, resulting in huge crystals. In a network solid, each atom is covalently bonded to all the surrounding atoms. The particles are held together too strongly to allow movement from place to place but the particles do vibrate about their position in the structure. With an increase in temperature, the particles gain kinetic energy and vibrate faster and more strongly.

The attractive force in solids need not be stronger than in liquids or gases. For example the forces between solid helium particles at degrees C are still very weak. By comparison, the forces between iron vapour particles requires very high temperatures are very strong. If you compare different substances that are at the same temperature, then the average kinetic energy of the particles will be the same i.

Attractive forces don't get weaker when a substance moves from the solid to the liquid to the gas state, rather the kinetic energy of the particles increases implying faster motion , allowing them to overcome the attractive forces.

Explore the relationships between ideas about movement of particles in the Concept Development Maps - Chemical Reactions, States of Matter. Aim to adopt teaching strategies that promote dissatisfaction in students with their existing ideas, and promote a scientific conception that is plausible, consistent and useful in a variety of situations. It is important to ascertain the majority of students' prior views at the commencement of teaching to establish their existing understanding of the particle model of matter.

Ask students for their ideas about the size of atoms compared with other small things such as cells, bacteria and viruses. This can be done by asking them to draw the relative size of these on the same scale a scale where a human cell is the size of a page or poster. Bring out the idea that atoms are so much smaller again. Look for other activities that can help reinforce the idea that particles are very, very small.

Show students the conventional drawings of particles in solids, liquids and gases and ask them if and how fast they think they are moving. For more information see: Conservation of mass. With a little encouragement, a class can usually work out by discussion that the particles in gases must be hitting the bottom of the flask harder than the top and hence that they are affected by gravity.

As particles cannot be directly observed, much of the teaching involves looking for apparent problems or inadequacies with the sorts of static pictures of particles given in earlier years. Encourage students to identify these and talk through possible explanations. Some prompts:. The gas particles have big distances between them.

Solid — In a solid, the attractive forces keep the particles together tightly enough so that the particles do not move past each other.

Their vibration is related to their kinetic energy. In the solid the particles vibrate in place. Liquid — In a liquid, particles will flow or glide over one another, but stay toward the bottom of the container.