1st Year Science – Chemistry ‘States of Matter’ 1st Year Science – Chemistry

Introduction – States of Matter All substances in our world are one of 3 things... Solid Liquid Gas These are the three states of matter What is matter? What Substance can be all 3 states? Matter is anything that has mass and occupies space Water

Introduction – States of Matter

Properties of States of Matter Properties of Solids, Liquids and Gases Solids Liquids Gases No Definite Shape Take the shape of their container No Definite Shape Take the shape of their container Shape Definite Shape Volume Definite Volume Definite Volume No Definite Volume Cannot be compressed Cannot be compressed Can be compressed Compression Ability to flow Cannot flow Can flow Can flow

Changes of State (of Matter) This is when a substance can change from one state to another, i.e... Solid to liquid Liquid to Gas Gas to liquid Liquid to solid Most substance’s state can be changed A good example of this is water. It can be all three states. *Melting point* *Boiling point*

Changes of State Lets have a look at water and how it can ‘change state’ No new substances are formed during a change of state Freezing(0⁰C) Boiling(100 ⁰C) Liquid to solid Liquid to Gas Solid - Ice Liquid - Water Gas - Steam Solid to Liquid Gas to Liquid Melting Condensing

Evaporation Liquids don’t always have to be boiled in order to change to a gas. Puddles/sea/river/lake water can quickly disappear when the sun comes out. How evaporation occurs Water molecules at the surface of the liquid gain enough energy from the sun to escape as a gas into the atmosphere

Condensing Steam from the kettle gathers as droplets on the surface of the glass Clouds are formed when evaporated water is cooled and then turned back into water droplets. Condensing is the cooling of a gas in order to turn it into a liquid form

Diffusion A good example of diffusion is when we can smell something but cannot see it e.g. your mother’s cooking, tea bags or........ The gas particles spread throughout the room Diffusion is how the particles in liquids or gases spread throughout the area in which they are placed.

Molecules in Solids and Liquids Molecules are constantly moving or ‘vibrating’ Molecules Come together and push apart continually (to and fro) This is what gives solids a definite shape Liquids When molecules of a solid are heated they vibrate faster and get more excited until they come apart Molecules now act in a random manor (slip and slide) and the definite shape is no more. The more slipping and sliding of molecules means the more easily the liquid flows.

Lets have a look at water and how it can ‘change state’ Changes of State Lets have a look at water and how it can ‘change state’ _________ _________ Solid - Ice Liquid - Water Gas - Steam _________ _________

The Properties of the Three States of Matter Properties of Solids, Liquids and Gases