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