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Types of Matter. Matter must. Have mass Have volume (take up space). Matter exists in three phases. Solids (s)- fixed shape & volume Liquid (l)- fixed volume, takes the shape of the container Gas (g)- takes both the volume and the shape of the container. - PowerPoint PPT Presentation
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Types of Matter
Matter mustHave massHave volume (take up space)
Matter exists in three phasesSolids (s)- fixed shape & volume Liquid (l)- fixed volume, takes the shape of
the containerGas (g)- takes both the volume and the shape
of the container
Matter is divided into 2 categories.Pure Substances
Fixed compositionUnique set of properties
MixturesComposed of two more substances physically
mixed
Pure SubstancesElements-type of matter than cannot be
broken down into two or more pure substancesElements can be divided into many categories
Metals Nonmetals Metalloids Families (Periodic Table)
Compounds-more than one element Have new properties after chemically
combined
MixuresHomogeneous-composition is the same
throughoutA solution is a liquid homogeneous mixture
made of solvents & solutes.Most solvents are liquids; however it can be a
gas
Heterogeneous- does not have a uniform composition
Separation TechiquesWe are going to look at 3 types. There are more.Filtration
Used for a heterogeneous solid-liquid mixtureDistillation
Homogeneous solid-liquid mixtureAlso liquid-liquid mixtures in which one liquid can
be evaporatedChromatography
Liquid-liquid mixtureLiquid-gas mixtureGas-gas mixture
Significant FiguresUncertainty of at least one unit in the last
digit2.00 mL = 3 SF2.0 mL = 2 SF2 mL = 1 SF0.002 mL= 1 SF
RulesZeros appearing between nonzero digits are significantZeros appearing in front of all nonzero digits are NOT
significant.Zeros at the end of a number and to the right of a
decimal point are significant.A decimal point placed after zeros indicates that they are
significant.Trailing zeros without decimals are questionable
75000 may be 2-5 SF 7.5 x 104 = 2 SF 7.50 x 104= 3 SF
Assume not significant in the book therefore 75000= 2SF
RulesMultiplying & Dividing
The # of SF in the result is the same as quantity of smallest # of SF
Adding & SubtractingThe number of decimal places in the result is the same with
the smallest decimalRounding
If less than 5… leave last digit unchangedIf greater than 5…add one to the last digitIf equal to 5…round even
Round 14.575 to 2SF= 14
RulesMultiple Operations
Carry out all steps with complete number of digits
Go back to find the # of SF at each stepRound at the end
ALWAYS SHOW WORK AND USE YOUR UNITS!!!
How many Sig Figs?1. 0.00800 in2. 52.000 nm3. 800 ns4. 4.30 x 104 kg5. 5060 g
Solve the problem with correct SF. Box in your answer.
1. 2.505 x 0.0920 x 451.08=
2. 0.0810 + 7.168 + 1.50 =
3. 5.20/8.973=
***When putting in your calculator remember to use () to make calculator do order of operations correctly.
When you make a conversion, choose the factor that cancels out the initial unit.
The actual conversion factor does not count on significant figures
Use the number of significant figures in the initial measurement given
Remember what % means mathematically. When given a % use the unit shown in the problem.52% mL = 52 mL/ 100 mL0.07% L = 0.07 L/ 100
Conversions
3 hr to sec
5.27 Mg to lb (Mg= mega grams)
0.53 mi to m
55.25 mi to km
11.6 mL to in3
Examples
Every pure substance has its own unique set of properties
Chemist use these properties for identification
2 ways of grouping these properties
Properties of Substances
Intensive Properties (do not depend on amount) ***chemist use these to identifyThese are a few examples
Density Melting pt Boiling pt
Extensive Properties (depend on amount )MassVolume
Intensive & Extensive Properties
Physical- do not change the substanceTheses are just a few examples
Density Melting pt Boiling pt Solubility Color
Chemical-when a new substance is formedReactivityFlammability
Physical & Chemical Properites
Denisty= mass/volumeMass= gramsVolume= cm3, mL, L
Be sure to show all work and units!!!!!
Density
The density of Al is 2.70 g/mL. What is the volume of 8.21 grams?
The density of Hg is 13.5 g/mL. How many grams are in 5.0 mL?
Examples
A sample of metal in a small weighing dish had a mass of 59.61g. The dish had a mass of 0.58 g. When the metal was added to the water, the water level rose 9 mL.
What is the mass of the metal?
What is the density of the metal?
Examples
A sample of metal with a mass of 10.06g was placed in a flask with a volume of 65.0 mL. To fill the flask, 35.7 g Hg (density= 13.5 g/mL) must be added to the metal. What is the density of the metal?
Examples
Atomic Mass= mass on the periodic tableAvogadro’s Number
Symbol NA
6.022 x 1023
It represents the number of atoms of an element in a samples whose mass in grams is equal to the atomic mass of that element
6.022 x 1023 H atoms= 1.008 g H6.022 x 1023 N atoms = 14.001 g N
Moles to grams to particles
Find the mass of a N atom
Find the number of N atoms in 7.00 grams.
Examples
Moles1 mole = Avogadro’s Number1 mole = 6.022 x 1023
Molar MassUnits are g/molSame as formula mass
Moles and Molar Mass
13 g of caffeine, C4H5N2OConvert to molesConvert from moles to atomsConvert from atoms to Number of Carbon
atoms
Examples