Post on 26-Dec-2015
Aim: What is matter?
MatterIncludes solids, liquids and gases
Ex.: basketball, juice, airHas mass and volume
Mass: amount of matter in an objectUnits- grams (g), kilograms (kg)Objects with more mass have more
weight
Volume: amount of space an object takes upUnits-Cubic cm, cubic inchesTwo ways to find volume: (solid)
V= L x W x HWater displacement method
•Liquid:•Use a graduated cylinder•Meniscus-bottom level of the curved line
•Solids:•Two Methods:
1. V=L x W x H• Used for regularly shaped objects
2. Water Displacement Method• Used for irregularly shaped objects• Object placed in water and the water rises• The amount of the water goes up equals the
volume of the solid
WB Pg 229 # 1-3
1. Any solid, liquid, or gas is _______________.
2. The amount of matter in a object is called ________.
3. The amount of space taken up by an object is called its _______________.
Aim: How do we find the mass of an object?
Triple Beam Balance:Measures the mass of an object in
gramsHas three beams
OnesTensHundreds
Balance needs to be at zeroPointer needs to be even with zeroWe use counter weight to adjust the scale
Place object on the pan
Move the 100 grams beam first to see if the object needs more weightIf the pointer stays up the object is more weightNeed to move the 10 beam, the ones beam
If the pointer stays down the object is less weightNeed to return the 100 beam to zero and move the tens beam, then ones beam
LETS PRACTICE!
Aim: What is density?
Density:The amount of mass in a certain volume of material
Formula: D=M V
Unit=g/cm3The less dense object floatsThe more dense object sinksIf the density of the object has the same
density of the water, it “hovers” in place
WB Pg 229 # 4-54. The amount of mass in a given
amount of space is the __________ of an object.
5. Liquids will form layers in order of density-the _______ dense liquids floats on the more dense, if the two liquids do not mix together.
Examples:1. Mass= 40 g Volume=10cm3
2. Mass= 25g Volume= 5cm3
3. Mass= 63 gVolume= 9cm3
Aim: What are physical properties?
Physical PropertiesProperties are things we can observe with our senses
Not changing the identity of the substance
Odor, hardness, color, shineDensity can be used to tell substances apart
Ability to conduct electricityMagnetismStates of matter (solid, liquid or gas)
Size and shape
WB Pg 229 # 6-96. Properties such as color and odor are
__________ properties.7. Physical properties can be observed
without changing the ________ of the substance.
8. Something that has a definite shape and volume is called a(n) ______________.
9. Something that keeps the same volume but fills the shape of its container is called a(n) ______.
Aim: What is a physical change?
Physical ChangesA change in size, shape or state without forming a new substance
Different substances change state at different temperaturesMelting Point- solid to a liquidBoiling Point- liquid to a gas
WB Pg 229 # 10-1410. Any change that does not produce a new
substance is a __________.11. The temperature at which a substance
changes from a solid to a liquid is called the ________________.
12. The temperature at which a substance changes from a liquid to a gas is called the ______________.
13. The particles of a substance will move faster if ________ is added to them.
14. When the particles of a substance move about faster, they spread out, causing the substance to ___________.
Aim: What are the types of mixtures?
MixturesAny combination of two or more substances in which the substances keep their own properties
5 Types of Mixtures:1. Suspensions
Parts separate upon standing Need to shake well before using Example: oil and water
2. Emulsion:Is a suspension of two liquids that do not mix together
3. Colloids:Contain particles or droplets that stay mixed in another substance
Example: fog-fine water droplets in air
Liquid-in-gas colloid
4. Solutions:mixture of one substance dissolved in another so that the properties are the same throughout
All parts have the same properties (color, odor, taste)
Soluble- can be dissolvedSolute- substance that becomes dissolved
Solvent- part that dissolves a substance
Example:Tea: solute=tea particles
solvent=waterSolutions can contain any combination of solids, liquids and gases
5. Alloys:Solutions of one or more metals and other solids
Made by heating, melting and mixing the parts together
The solution then cools and hardens
Examples:Gold jewelryFancy silverware Pennies
Aim: How are elements and atoms related?
ElementsPure substances that can not be broken down into simpler substances
All matter is made up of elementsCan be solids, liquids or gasesMixed physically
Ex: oxygen and nitrogen in the airMixed chemically
Ex: salt (sodium and chlorine)
AtomsElements are made up of atomsSmallest particle of an elementEach element is made up atoms that
have its own special propertiesAtoms in one element are different
than the atoms in another elementAtoms have the same chemical
properties of that element
WB Pg 235 #1-61. All matter in the world is made of ______________.2. Elements can be chemically combined to form
__________ like salt and sugar.3. The smallest particle of an element that has the
same chemical properties as the element is an _________.
4. For centuries, scientists have been trying to find out what is inside ___________.
5. The idea that tiny __________ make up matter came from the Greek philosopher Democritus.
6. John Dalton concluded that gases were made up of solid particles with _________ spaces between them.
Aim: What are electrons, protons and neutrons?
All atoms have a nucleus (densest part)Rest of the atom is empty spaceNucleus contains 2 parts:
1. Protons-positive charge2. Neutrons-no charge or neutral
We can find the atomic mass of an atom by adding the # of protons and neutrons
Electrons move around the nucleus Negative charge
WB Pg 235 # 7-107. The densest part of an atom is the ________
where most of the atom’s mass is located.8. A positively charged particle inside an atom’s
nucleus is a(n) ____________.9. A particle with no charge inside an atom’s
nucleus is a(n) _________________.10. A negatively charged particle that moves
around an atom’s nucleus is a(n) __________.
Aim: How does the periodic table help identify properties of elements?
Periodic TableCreated by Dmitry Mendeleyev in 1868Discovered a repetitive pattern
amongst elements propertiesLeft blanks in table to continue the
patternNew elements were discovered to fill
these blanks112 elements known todayArranged in order of increasing atomic
number
Vertical columns contain elements that are chemically alike
Each row called a periodAlso grouped into metals,
nonmetals, metalloidsElements are also identified as solid,
liquid or gas
Metals¾ of elements are metalsConduct electricity
NonmetalsPoor conductors of heat and electricityMost nonmetals are gases or solids at
room temperatureBromine-is a liquidSolids-brittle, not bendable
MetalloidsProperties fall in between those of metals and nonmetals
Make computer chips and circuitsExamples: boron, silicon
Chemical ChangesProduce substances that have new and
different properties from the original substance
Signs of chemical change:Change in colorHeat and light given offPowdery solid settles out of a liquidGas is produced
Compounds:Chemical combination of 2 or more
substancesHave its own properties different from
the original substancesExample: rust or iron oxide
Iron and oxygen have combined to form a new substance
Is crumbly brownish solid, with no shineIron is a durable solid, does not
crumble, but when mixed with oxygen its properties change
Chemical BondsLinks that atoms can form with another
atomResult from electrical attraction
between the atomsAtoms of different elements bond
togetherChemical formula represents the bondsA certain # of one kind of atom always
bonds to a certain # of anotherEx: CO2
One carbon atom, two oxygen atoms
Homework:Tell how many atoms of each element there are in each chemical bond.
1.Water-H2O 2.Salt-NaCl3.Glucose-C6H1206
4.Methane-CH4
5.Sulfate-S04
Covalent Bonds Ionic BondsForm when 2
nuclei attract the same electrons
Type of chemical bond
Two atoms share electrons
Examples:H2O
O2
An atom of a nonmetal can take an electron from an atom of a metal
When this happens we get an ion
Form because opposite charges attract
Examples:NaCl
Chemical ReactionsA substance is turning into a new
substance because of a chemical changeOriginal substance-reactantNew substance-products3 types:
1. Synthesis reaction: 2 separate elements or compounds
join together to form a new compound
Ex: rusting of steel wool Iron (Fe) + Oxygen (O)=Fe2O3
2. Decomposition reaction:Breaking down of a complex substance
into 2 simpler substancesEx: H2CO3 (Carbonic Acid) CO2 +
H20
3. Replacement reaction:Elements switch or replace another
elementEx: 2AgCl + Pb PbCl2 + 2Ag
Silver Chloride + Lead Lead Chloride + Silver
Chemical property-way of describing a substance by how it reacts to other substances
1st column of the periodic table has very reactive metals
The last column has the most stable elements (noble gases)
Acids BasesProperties:
Sour tasteCorrosive-wear
away metalCan burn skin
Indicator-litmus paperBlue turns to
red
Properties:Bitter taste, slippery
feel, poisonous, many can burn skin
Can dissolve hair, wool, grease and fingernails
Used to clean drainsHelp digest foodMild bases-soap,
shampooEx: ammonia (powerful)Red litmus turns blue
Exothermic reactionsChemical reactions that give off heat
Not all produce a flame
Endothermic reactionschemical reaction that needs to take in heat/energy in order to occur
Once heat/energy is removed, the reaction will stop