Matter

MatterMrs. Horn 5th Grade Science2nd Nine WeeksWhat is matter?Matter is all around youMatter is anything that has mass and takes up spaceAll matter is made up of the same set of building blocks- the chemical elementsElementsA material that cannot be broken down into anything simplerMade of only one kind of atomScientists know of more than 112 elementsCan be classified as metals, nonmetals, or metalloids, and noble gases

The Periodic table of elementsCreated by Dmitri Mendeleev in 1869Shows elements repeating properties in periods, or cyclesEach element has a symbol Most are one or two letters- Example: Carbon-C The first letters are always capitalized; second letter never capitalized- Example: Nitrogen- N, Helium- He The Periodic table of elements

metalsShinyConduct heat and electricityBend easilyExamples: Copper, Zinc, Sodium, Magnesium , TinNonmetalsDullPoor conductors of heat and electricity BrittleExamples: Oxygen, Nitrogen, Carbon, HydrogenNitrogen, Oxygen, and Hydrogen are all gases at room temperatureCarbon is solid at room temperature

metalloidsHave come properties of metals and some of nonmetalsExamples: Silicon, Arsenic, and Boron8 knownNoble gasesOdorlessColorlessLow chemical reactivityFound on the Periodic Table in group 18Include: Helium, Neon, Argon, Krypton, Xenon, and RadonAtomsSmallest unit of an element that still has the properties of that elementAn atom is made up of:Protons- positive charge; # of protons is called atomic numberNeutron- no charge (neutral); # of neutrons = mass # - atomic =Protons and neutrons are found in the nucleus Electrons- negative electric charge; # of electrons and protons are equal so atoms have no chargeIf you add up the mass of all the protons and neutrons you have found the atoms atomic mass

atoms

What are compounds?Forms when two or more elements combine chemicallyExample: Water is formed by the combining of two Hydrogen atoms and 1 Oxygen atomExample: Sodium Chloride (Table Salt) is formed by the combining of 1 Sodium atom and 1 Chlorine atomCompounds have properties different from their individual elementsAll compounds have chemical names and many also have common names (Example: iron oxide= rust); The chemical name tells which elements make up the compound (Example: Fe2o3= iron oxide or rust; 2 atoms of Iron and 3 atoms of Oxygen)moleculesForms when two or more atoms join together and share electronsExamples: Oxygen- O2 and water- H2OStates of matterThree common forms that matter takes: solid, liquid, gasEach state has its own propertiesYou interact with all three forms each daysolidParticle have little freedom to moveParticles vibrate in placeStays in a definite shape with a definite volume no matter its containerShape and volume will not change unless something changes it by means such as breaking or heatingliquidParticles move more freely than in a solidParticles are close together but can flow past each otherTakes the shape of its containerHave a definite volume but not a definite shapegasParticles are not close together and can move past each other very easilyHas no definite shape or volumeAt room temperature, gases move around to fill their containerIf the volume of the container increases, the gas expands to fill it; this allows gases to inflate things such as tires and ballsStates of matter

Physical and Chemical PropertiesPhysical PropertiesSomething that can be observed about an object without changing the identity of the objectMass, volume, length and weight describe the amount of matterDensity, color, hardness, odor, magnetism, boiling point, and freezing point are some other physical properties Physical properties may be classified as intensive or extensive Intensive properties depend on the amount of substance present (Examples: density, boiling point, freezing point, magnetism)Extensive properties depend on the amount of substance present (Examples: mass, length, volume, and weight)MassAmount of matter in an objectCompares the amount of matter in a sample to standard amountsCan be measured on an equal pan balanceAmount of matter in the sample and the standard pieces must be the sameMeasured in kilograms or grams (one kilogram = 1,000 grams)Mass of an object is always equal to the sum of the masses of the pieces of the objectExample: If you were to empty all items out of your backpack and place them and the empty backpack on one side of the balance, and the same backpack with all of the same items in it on the other side, the two masses would be equal

WeightHow strongly gravity pulls on an objectThe more mass an object has, the more weight it has Measured in newtons (N)One newton is equal to 0.225 pounds (lbs)An objects weight depends on the planet it is on because the pull of gravity is greater on planets with more mass; an objects mass is the same on any planet volumeMeasures how much space matter takes upTo find the volume of a regularly shaped object use the following formula: L x W x H (length x width x height)Irregular shaped objects may be measured by placing them in a graduated cylinder of water; the change in the water level after the object is placed in tells its volumeVolumes of liquids are measured in milliliters (mL) by using a graduated cylinder, a beaker, or a measuring cupVolume of solids is measured in cubic centimeters (cm3)

DensityAmount of mass for each cubic meter (cm3) of a substanceTo calculate a substances density you divide its mass by it volume

Floating and sinking- buoyancyObjects can float as a result of buoyancy, the resistance to sinkingIf an object is denser than the liquid, then the object can pusher harder and it sinks; if the liquid is denser than the object, then the liquid can push harder and the object floatsBuoyancy depends on density and shapeIf you change the mass or the volume of an object, you can change whether it will float

Floating and sinking- surface tensionMany liquids have a property called surface tensionIn water, every particle pulls toward the other particles and creates a skin on the surface (surface tension)If an object is spread over the surface, it can rest on this skin even if it would not normally floatIf an object is not spread out enough, it will break the skin and sinkBoiling and freezing pointThe temperature at which a substance boils is called its boiling pointAt its boiling point, a substance changes state from a liquid to a gasWater boils at 100 Celsius (212 Fahrenheit) The temperature at which a substance freezes is called its freezing pointWater freezes at 0 Celsius (32 Fahrenheit)Boiling point and freezing point remain consistent no matter the amount of substance presentChemical PropertiesDescribes the way a substance reacts with other substancesCan only be seen when matter is changed into a new kind of matterElements in the same column on the periodic table have similar chemical propertiesFlammability- chemical property that describes its ability to catch on fire or burnCorrosion- when metals combine with nonmetals from the environment Ex: Iron corrodes by rustingBurning Ex: Wood burns and becomes ashTest prepWater, salt, and rust are all examples of ___________.

ElementsMetalsCompoundsMolecules

Test prepWhich is not an example of an element?

NaAluminumIronCO2Test prepWhich of the following is an example of an element?

CO2GoldCarbon dioxideSodium chlorideTest prepWhich of the following statements explains why aluminum is an element?

It conducts electricity.It does not dissolve in water.It can be recycled and reused.It is made of only one kind of atom.Test prepWhich term describes a substance made of two or more elements chemically combined?

MixtureCompoundSolutionAtom

Test PrepWhat happens when two different elements chemically combine?

A new substance forms with the properties of one of the elements.The new substance takes on the properties of the larger element.The newly formed substance becomes a gas.A new substance forms, having new properties.