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How to differentiate between physical and chemical properties

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How to differentiate between physical and chemical properties. Alexis Roberts, Yary Urena , Quintessia Green, and Natalia Casas Team 5 3 rd Period. Physical Properties. - PowerPoint PPT Presentation

Text of How to differentiate between physical and chemical properties

How to differentiate between physical and chemical properties

How to differentiate between physical and chemical propertiesAlexis Roberts, Yary Urena, Quintessia Green, and Natalia Casas

Team 5 3rd PeriodPhysical PropertiesPhysical Characteristics can be observed and measured without changing the kind of matter being studied.The following physical properties can used to help identify a substance.

Melting PointMelting Point- the temperature at which a solid can change to a liquid.The temperature at which a pure substance melts does not change under constant conditions.The melting point of a pure substance can be used as a physical property.

Boiling PointBoiling Point- The temperature at which a liquid boils

During the process of boiling, a substance changes from a liquid to a gasBoiling begins when the liquid starts to form bubbles, which grow larger, rise to the surface and burst.Boiling point is unchanging under constant conditions for a given substance, so it can used as a physical propertyAs long as the substance is boiling, the temperature remains constant

DensityDensity- a property that describes the relationship between the mass of the material and its volume.

Substances that have higher densities contain more matter in a given volumeThe density of a substance will stay the same no matter how large or small the sample of the substance isFor example, the density of lead is much greater than the density of aluminum

Color The color is used to identify substances and other properties The color itself is not a significant identifier of a substance Whenever there is no color, it is also a physical propertyChemical Properties Chemical Properties are also used as identifiers of a substance These chemical properties can only be recognized whenever the chemicals react to each other or whenever they dont The chemical property of one substance usually involves its ability to react according to another specific substance or not

Reacting with Oxygen An example of a chemical property is the ability of a substance to burn, this chemical property allows a substance to react quickly with oxygen to produce light and heat This reaction occurs when iron begins to rust or apples turn brownReacting with Acids When a substance has the ability to react with substance, it is also a chemical property Some metals react with react with many acids to form compoundsNot all metals react with all acidsBases react with acids to form water and to neutralize the acidPhysical ChangesPhysical changes do not change the composition of a substance, only the physical properties.Evidences of a physical change include

10Change in State of MatterWhen a substance changes from one state to the other (liquid to solid, liquid to gas, etc.)the composition of the substance stays the sameEx. Of change of state: melting ice creamWhen a substance changes from gas solid or solid gas, that change of state is called sublimationThis is still a physical change because composition of the substances stays the same

Change in Shape and SizeWhen a substance changes in a size or shape (Cutting, tearing, dissolving, stretching, or wrinkling) its composition stays the sameEX: shredding paper, dissolving sugar in water, denting a piece of metal

Chemical ChangesChemical changes result in the formation of one or more new substances with new chemical and physical properties.Evidence that a chemical change may have occurred include

Color ChangeWhen a Substance changes color it shows the chemical reaction & how the chemical composition has changed, for example: Iron turning reddish-brown when it rustBut it is possible that a substance can have a color change without a chemical change, for example: Putting food coloring in water

Temperature ChangeWhen 2 Substances Are Combined, There Could Be An Increase Or Decrease In Temperature Like When Fire Burns Wood, The Temperature INCREASES

Its Is Possible To Have A Temperature Change WITHOUT A Change Without A Chemical Change Like Warming Up The Water In A PondFormation Of A PrecipitationWhen TWO Solution Combine They May Form A Solid Substance. This Solid Substance Is Called A .. PRECIPITATE & Indicates That A Chemical Change Has Occurred.When Carbon Dioxide I Combined Is Combined With Aqueous Calcium Hydroxide (Limewater); Solid Calcium Carbonate (Chalk) Is Formed As The Particles, Appearing As Cloudiness In The Solution Or As A Sold Which Settles To The Bottom Of The Container.Formation Of a GasWhen A Solid Or Liquid Substance Are Combined, They Form GAS BUBBLESThe Formation Of The Gas May Indicate That A Chemical Reaction Has Taken Place, Like When Vinegar Is added To Baking Soda, It Forms CARBON DIOXIDE BUBBLESIt Is Possible To Form Gas WITHOUT A Chemical Change, Like When Is Heated To Boiling

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