2.1_matter.pptx
TRANSCRIPT
THE STRUCTURE OF THE ATOM
THE STRUCTURE OF THE ATOMMATTER
[email protected] is anything that occupies space and has massMatter is made up of tiny and discrete particles (atoms, molecules, ions)There are spaces between these [email protected]
AtomThe smallest particles of an element that can participate in a chemical [email protected]
MoleculeA group of two or more atoms which are chemically bonded [email protected]
IonA positively-charged or negatively-charged [email protected]
DiffusionOccurs when particles of a substance move in between the particles of another substanceOccurs most rapidly in gases, slower in liquids and slowest in solids due to the different arrangement and movement of particles in the three states of [email protected]
[email protected] Kinetic Theory of MatterSOLIDDiagramArrangement of ParticlesThe particles are pack closely together in an orderly mannerForces of AttractionThere are strong forces between the particlesMovement of particlesThe particles can only vibrate and rotate about their fixed positionVolume and ShapeFixed volume and shapeCompressibilityCannot be [email protected]
LIQUIDDiagramArrangement of ParticlesThe particles are packed closely together but not in orderly arrangementForces of AttractionThe particles are held together by strong forces but weaker than the forces in a solidMovement of particlesThe particles can vibrate, rotate and move throughout the liquid. They collides against each otherVolume and ShapeHas a fixed volume but does not have a fixed shape. It takes the shape of the containerCompressibilityCannot be compressed [email protected]
The Kinetic Theory of MatterGASDiagramArrangement of ParticlesThe particles are very far apart from each other and in a random motionForces of AttractionWeak forces between the particlesMovement of particlesThe particles can vibrate , rotate and move freelyVolume and ShapeDoes not have fixed shape or volumeCompressibilityCan be compressed [email protected]
The Kinetic Theory of Matter
Inter-conversion of the states of [email protected] is heatedThe particles in solid gain kinetic energy and vibrate more vigorouslyThe particles vibrate faster as the temperature increases until the energy they gained is able to overcome the forces that hold them at their fixed positionThe solid becomes a liquidThis process is called meltingMelting point is the temperature at which solid turns to [email protected] is cooledThe particles in the liquid lose energy and move slowerAs the temperature continues to drop, the particles continue to lose more energy until they do not have enough energy to move freelyAt this point, liquid changes into a solidThis process is called freezingFreezing point is the temperature at which liquid turns to [email protected]@smart.chempanel
Heating Curve Temperature, CTime, sMelting PointABCDThe curve shows the change in temperature when solid naphthalene meltsAt Point A : Naphthalene exist as solidWhen solid is heated, heat energy is absorbedThis causes the particles to gain kinetic energy and vibrate fasterThe temperature increases from point A to point [email protected]
Temperature, CTime, sMelting PointABCDAt Point B : Solid naphthalene begins to melt During the melting process, the temperature remain constant It is because, the heat energy absorbed by the particles is used to overcome the of attraction between particles so that solid can turn into liquidThis constant temperature is the melting point of naphthaleneBoth solid and liquid are [email protected]
Temperature, CTime, sMelting PointABCDAt Point C : All the solid naphthalene has meltedFrom point C to point D, the particles in liquid naphthalene absorb heat energy and move fasterThe temperature increases from point C to point DThe particles exist as [email protected]
Temperature, CTime, sMelting [email protected]
Cooling Curve The curve shows the change in temperature when liquid naphthalene freezeTemperature, CTime, sFreezing PointEFGHAt Point E to F : The particles exist as liquidThe particles in the liquid lose kinetic energyThe particles move slower as temperature decreases
Temperature, CTime,sFreezing PointEFGHAt Point F :Liquid naphthalene begins to freezeThe temperature remain constantIt is because, the heat loss to the surrounding is exactly balanced by the heat energy liberated as the particles attract one another to form solidBetween point F and G : The particles exist as mixture of liquid and solid
Temperature, CTime,sFreezing PointEFGHAt Point G :The solid is cooledThe particles in the solid vibrate slower as the temperature decreases
Temperature, CTime,sFreezing PointEFGH