States of Matter Sara sultan 09/04/2019

Matter Matter is anything that occupies some space and has mass. Everything that surrounds us, such as air, food, water, plants, animals, vehicles, clothes and so forth is made up of matter. Definition of matter based upon its physical and chemical structure: ‘Matter is made up of atoms and molecules’. So, matter is the collection of particles. Particles have space between them. Particles of matter are continuously in motion. Particles of matter attract each other because of intermolecular force of attraction. Matter can exist in one of three fundamental states: solid, liquid, or gas. The states of matter take place due to the variations in the molecules of matter. 09/04/2019

Rigid matter that feels hard and maintains a fixed shape Solids Rigid matter that feels hard and maintains a fixed shape Particles tightly bound Can’t move freely Vibrate and twist Strong IMAF Two types: Crystalline and Amorphous Crystalline solids have a long order arrangement of particles, while the particles are randomly arranged in amorphous solids. 09/04/2019

Fluid matter that feels wet and maintains its volume but not its shape Liquids Fluid matter that feels wet and maintains its volume but not its shape Particles closely held Free flow from high to lower concentration Move and mix Moderate IMAF Unique properties: Surface Tension, Viscosity Surface tension is a force that acts on the particles at the surface of a liquid. Allows liquids to occupy minimum surface area. Viscosity is a liquid’s resistance to flow. 09/04/2019

Fluid matter that changes both shape and volume Gases Fluid matter that changes both shape and volume Particles loosely held Free flow in every direction Fill the entire available space Very weak IMAF Unique Properties: Diffusion, Brownian motion Diffusion is intermingling of substance by movement of particles from higher to lower concentration. 09/04/2019

Summary BASIS FOR COMPARISON SOLID LIQUID GAS Meaning Solid has structural rigidity and a firm shape which can’t be changed easily. Liquid flows freely, having a definite volume but no permanent shape. Gas do not have any shape but conform to the shape of the container Shape and Volume Fixed shape and volume. No fixed shape but has volume. Neither definite shape nor volume. Energy Lowest Medium Highest Compressibility Difficult Nearly difficult Easy Arrangement of molecules Regular and closely arranged. Random and little sparsely arranged. Random and more sparsely arranged. Fluidity Cannot flow Flows from higher to lower level. Flows in all directions. Molecular motion Negligible molecular motion Brownian molecular motion Free, constant and random motion. Intermolecular space Very less More Large Intermolecular attraction Maximum Minimum Sound speed Fastest Faster than gas but slower than solid Lowest among all Storage Don't need container, for storage. Can’t be stored without container. Needs closed container for storage. 09/04/2019

Effect of Heat on Particles When heat is added to a substance, the particles move faster. When heat is lost from a substance the particles move slower. The motion of the particles increases when temperature increases and vice versa. Heat energy transfers from high temperature matter to low temperature matter. Heat Effect Physical Expansion State change Chemical Decomposition 09/04/2019

Thermal Expansion Thermal expansion is the tendency of matter to change in shape, area, and volume in response to a change in temperature. Temperature is a function of the average molecular kinetic energy of a substance. When a substance is heated, the kinetic energy of its molecules increases. Thus, the molecules begin vibrating/moving more and usually maintain a greater average separation. The relative expansion divided by the change in temperature is called the material's coefficient of thermal expansion and generally varies with temperature. The coefficient of thermal expansion describes how the size of an object changes with a change in temperature. 09/04/2019

Change in States of Matter The matter changes its state from one form to another, when heated or cooled, which is covered under the physical change. So, given below are some processes through which the state of matter can be changed: Melting: Process of change of solid into the liquid. Freezing: The process which helps in transformation of liquid into solid. Vaporisation: Process used to change liquid into gas. Condensation: A process in which gas is transformed into liquid. Sublimation: When solid is changed into gas, it is called as sublimation. Disposition: The process through which gas is converted into solid. When the change is reversed exactly the same amount of heat is released. The heat energy involved in a change of state is called the latent heat. The latent heat of vaporisation is the amount of heat required to change one kilogram of a liquid to its gas (or vapour) at is boiling point. 09/04/2019