PROPERTIES OF MATTER 6th Grade Matter Unit

Characteristic Properties The properties that are most useful in identifying a substance are its characteristic properties. Remember the difference between physical and chemical properties. Physical properties can be observed! (with your eyes!) IDENTITY OF SUBSTANCE DOES NOT CHANGE! You can observe chemical properties only in situations in which the identity of the substance could change.

Types of Properties Physical: properties that can be observed without changing the IDENTITY of the matter A physical property is a property or characteristic of and object or substance that can be observed, described, and measured without changing the matter. Chemical: property of a substance that changes it into a NEW substance (changes the identity of the substance)

What are physical properties? A physical property is a property or characteristic of and object or substance that can be observed, described, and measured without changing the matter.

Mass The amount of matter Triple beam balance to measure Definition: The amount of matter Example: Triple beam balance to measure Measured in gram units

Volume Irregular objects: Water displacement Definition: how much space the matter takes up Example: Irregular objects: Water displacement Regular objects use measurement Liters or m3 1ml = 1cm3

Density D=M/V Mass per unit volume g/l, g/ml, or g/cm3 Definition: Mass per unit volume Example: D=M/V g/l, g/ml, or g/cm3 Lead is used for fishing weights because it is more dense than water

More information about density... Density = The amount of matter in a given space or volume Density = m Mass v Volume

More information about density... Most substances have a unique density: Water = 1.00 g/mL Gold = 19.32 g/mL (See page 13 in your book for a bigger list) Density < 1 - The object will float in water Density > 1 – The object will sink in water

State The form in which matter exists: solid, liquid, gas, or plasma Definition: The form in which matter exists: solid, liquid, gas, or plasma Ice = Solid Water = Liquid Helium = Gas Lightning = Plasma

Luster The ability to reflect light Shiny: more reflection Definition: The ability to reflect light Shiny: more reflection Dull: less reflection

Thermal Conductivity Definition: The ability to transfer thermal energy (heat) to something else Example: Coffee in a special cup to prevent heat transfer to our hands

Electrical Conductivity Definition: The ability to conduct electricity (the atoms allow their electron to move or flow) Example: Metals and non metals Conductors – good conductivity Insulators – no conductivity

The ability to be pounded into thin sheets Malleability Definition: The ability to be pounded into thin sheets Example: Aluminum can be pounded flat to make aluminum foil

Ductility The ability to be drawn into thin wires Definition: The ability to be drawn into thin wires Example: Copper is used to make wires

Solubility Definition: The ability for one substance to dissolve into another substance Example: Drink mix dissolves in water or sugar dissolves in coffee

Physical Changes A physical change is a change that affects one or more physical properties of a substance. Physical changes do not form new substances! EX: ice melting or sugar dissolving Physical changes are easy to undo.

Chemical Properties property of a substance that changes it into a NEW substance (changes the identity of the substance) Chemical properties describe a substance based on its ability to change into a new substance with different properties. Chemical properties cannot be observed with your senses. Chemical properties aren’t as easy to observe as physical properties. Examples of chemical properties: flammability and reactivity Ex: wood burns to form ash and smoke

Chemical Properties

Chemical Changes A chemical change occurs when one or more substances are changed into entirely new substances with different properties. You can observe chemical properties only when a chemical change might occur! Examples of chem. changes: baking a cake rusting

Clues to chemical changes Color change Fizzing or bubbling (gas w/odor production) Production of light Temperature (heat or cold) Precipitate (something new falls to the bottom) Chemical changes are not usually reversible! You can not undo fire.