Chapter 1Chapter 1

Matter, Energy, & ChangeMatter, Energy, & Change

1.1 What is Chemistry?1.1 What is Chemistry?•the study of matter and its transformations

Why study chemistry?

•learn fundamental physical models •gain technical perspective on current events •develop problem solving skills •appreciate life's little mysteries •Most of the building materials, clothes, and medicines today are

the result of chemistry

Branches of ChemistryBranches of Chemistry

Organic- Organic-

Inorganic-Inorganic-

Physical-Physical-

Biochemistry-Biochemistry-

Analytical-Analytical-

the study of the structures, synthesis, and reactions of carbon- compound

the study of the properties and reactions of inorganic compounds

•dealing with the physical properties of chemical substances

•study of the chemistry of living things

analysis of material samples to gain an understanding of their chemical composition and structure.

1.2 Matter and Energy1.2 Matter and Energy Matter______________________________Matter______________________________

•Matter – anything that has mass and occupies space•Inertia – the tendency of a body to stay at rest or to continue to move at the

same velocity, unless acted on by an outside force. A tractor trailer

has more inertia than a bicycle. A bowling ball has more inertia than

a tennis ball.

Mass and weight – used interchangeably, but there is a difference…

Mass -a quantity of matter, mass is measured using a balance

Weight-a measure of gravity's effect on something; use a scale to measure weight

Law of Conservation of Mass -Matter can neither be created nor destroyed in chemical or physical changes.

Example – sodium metal + chlorine gas ---> table salt, an edible crystal

_____Energy_________________________Everything that you see or sense is either matter or the interactions of energy and matter. True or False? Example: a book – a chunk of matter – hold it up – potential energy – drop it – kinetic energy

Energy – the ability to cause change or the ability to do work. (two types)

Kinetic –

Potential -

the energy of motionEx. baseball in flight, car rolling down a street

stored energy waiting to be releasedEx: gasoline, water behind a dam

Law of Conservation of EnergyLaw of Conservation of Energy Energy can change forms, but it cannot be created or destroyed by ordinary

chemical or physical changes

Gas Liquid Solid

•low density •easy to expand/compress •shape - fills container •quick diffusion•volume – container

•high density •hard to expand/compress •takes shape of container •middle diffusion•definite volume

•high density •hard to expand/compress •rigid shape •low diffusion•definite volume

1.3 States of Matter1.3 States of Matter

Plasma – A highly ionized gas. The fourth state of matter (it does matter). 99% of all matter in the universe is in a plasma state. Lightning, neon lights and fire are natural examples of plasma on Earth. Plasma tv’s? What are they all about?Plasma in flat-panel display technology that ignites small pockets of gas to light phosphors. Each plasma panel contains thousands of tiny tubes filled with ionized gas that, when excited by electricity, glow in different colors and intensities to create an image.

Properties and Changes of Matter

Properties – characteristics that enable us to distinguish one kind of matter from another

describe materials by listing their properties

Chemical properties vs. physical properties Measurement of a Ex: determining the flammability of gasoline involves burning it, producing

CO2 and H2O; wood burning, rusting iron, tarnishing silver, leaves changing colors, baking a cake

Measurement of a

Ex: density, color, boiling point, volume, temperature, and mass.

chemical property involves a chemical change.

physical property may change the arrangement but not the structure of the molecules of a material.

Intensive properties vs. Intensive properties vs. extensive propertiesextensive properties

•Extensive properties change when sample size changes; intensive properties don't.

Mass of WaterMass of Water 100.0 g100.0 g 10.0 g10.0 g

Volume of WaterVolume of Water 0.100 L0.100 L 0.010 L0.010 L

Temperature of WaterTemperature of Water 25 C25 C 25 C25 C

Density of WaterDensity of Water 1.00 g/ml1.00 g/ml 1.00g/ml1.00g/ml

Chemical Change vs. Physical Change

•A chemical change occurs when

Ex. chemical change: sodium metal + chlorine nonmetal --> table salt (crystal, white, edible) Ex. physical change: cutting paper, chopping wood, freezing water

Signs of a chemical change

a substance is converted into a different substance

• evolution of heat and light•production of a gas

• formation of a precipitate

Energy and Changes in Matter - Energy and Changes in Matter - Chemical reactions involve energyChemical reactions involve energy

ExothermicExothermic

releases energyreleases energy

reactants --> products + heatreactants --> products + heat

water(l) → ice(s) + heatwater(l) → ice(s) + heat

Graph:Graph:

EndothermicEndothermic

absorbs energyabsorbs energy

reactants + heat ---> productsreactants + heat ---> products

ice(s) + heat → wate(l)ice(s) + heat → wate(l)

Graph:Graph:

Water (reactants)

Ice (products)

Energy

heat

ice (reactants)

Water (products)

Energyheat

Examples of Exothermic Examples of Exothermic ProcessesProcesses

making ice cubesmaking ice cubes formation of snow in clouds formation of snow in clouds condensation of rain from water condensation of rain from water vaporvapor a candle flame a candle flame mixing sodium sulfite and mixing sodium sulfite and bleach bleach rusting iron rusting iron burning sugar burning sugar forming ion pairsforming ion pairs combining atoms to make a gas combining atoms to make a gas

moleculemolecule mixing strong acids and watermixing strong acids and waternuclear fissionnuclear fission

Examples of Endothermic Examples of Endothermic ProcessesProcesses

melting ice cubesmelting ice cubes conversion of frost to water conversion of frost to water vapor evaporation of watervapor evaporation of water forming a cation from an atom forming a cation from an atom in the gas phasein the gas phase baking breadbaking bread cooking an eggcooking an egg producing sugar by producing sugar by photosynthesisphotosynthesis separating ion pairsseparating ion pairs splitting a gas molecule apartsplitting a gas molecule apart mixing water and ammonium mixing water and ammonium nitrate melting solid saltsnitrate melting solid salts

1.4 Classification of Matter

Separate physically

Matter

MixturesPure

Substances

Heterogeneous Homogeneous

Suspension

Compounds Elements

Solution Colloid

Separate chemically

MixtureMixture

combination of two or more kinds of combination of two or more kinds of matter, but each retains its own matter, but each retains its own physical propertiesphysical properties

HeterogeneousHeterogeneous

composition is not uniform where composition is not uniform where samples are differentsamples are different

HomogeneousHomogeneous

Uniform composition; every sample is Uniform composition; every sample is the samethe same

SuspensionSuspension

Solid in liquidSolid in liquid

muddy water, granitemuddy water, granite

SolutionSolution

small particles that won’t scatter lightsmall particles that won’t scatter light

ex: air, salt waterex: air, salt water

ColloidColloid

particles larger than molecules, particles larger than molecules, scatterlightscatterlight

Shaving cream, starch waterShaving cream, starch water

Pure SubstancePure Substance

homogeneous sample of matter that homogeneous sample of matter that always has the same compositionalways has the same composition

CompoundCompound

substance that can be decomposed substance that can be decomposed into 2 or more substances by chemical into 2 or more substances by chemical changechange

Ex: NaCl, H2O, C6H12O6, CO2Ex: NaCl, H2O, C6H12O6, CO2

ElementElement

substance that cannot be broken down substance that cannot be broken down by ordinary chemical changeby ordinary chemical change

Ex: Au, Cu, Ni, NaEx: Au, Cu, Ni, Na

1.5 The chemical elements1.5 The chemical elementsThe periodic table compactly shows relationships between elements, and features are:

Periods are horizontal rows on the table. - Have the same number of electron shells

Groups (or families) are columns on the table. - Have similar chemical properties.

Blocks are regions on the periodic table

www.periodictable.com

Types of MetalsTypes of Metals Alkali MetalsAlkali Metals (Group IA, first column ) (Group IA, first column )

soft, extremely reactive metals soft, extremely reactive metals react with cold water to form hydrogen gas react with cold water to form hydrogen gas form +1 ions form +1 ions Li, Na, K, Rb, Cs, FrLi, Na, K, Rb, Cs, Fr

Lithium SodiumPotassium

Types of MetalsTypes of Metals alkaline earth metalsalkaline earth metals (Group IIA, (Group IIA,

second column): second column): soft, reactive metals soft, reactive metals compounds are a major component of compounds are a major component of

earth's crust earth's crust form +2 ions form +2 ions Be, Mg, Ca, Sr, Ba, RaBe, Mg, Ca, Sr, Ba, Ra

Magnesium Barium Beryllium

Types of MetalsTypes of Metals Transition Metals (columns 3-12)Transition Metals (columns 3-12)

hard, dense metals hard, dense metals less reactive than Group IA and IIA less reactive than Group IA and IIA

Nickel Gold Chromium

Types of MetalsTypes of Metals Rare earth metalsRare earth metals are the elements are the elements

at the bottom of the table. at the bottom of the table. lanthanides (top row) lanthanides (top row) actinides (bottom row) actinides (bottom row)

Lanthanide Uranium

NonmetalsNonmetals

halogenshalogens (Group VIIA, next-to-last column): (Group VIIA, next-to-last column): poisonous and extremely reactive nonmetals poisonous and extremely reactive nonmetals fluorine and chlorine are yellow-green gases fluorine and chlorine are yellow-green gases bromine is a volatile red-brown liquid bromine is a volatile red-brown liquid iodine is a volatile blue black solid iodine is a volatile blue black solid all form -1 ions all form -1 ions

noble gasesnoble gases (Group 0, last column) (Group 0, last column) all are all are monatomicmonatomic gases gases a. k. a. inert gases; almost completely unreactive a. k. a. inert gases; almost completely unreactive

Properties of Metals - MacroProperties of Metals - Macro

malleablemalleable: can be hammered into thin : can be hammered into thin sheets sheets

ductileductile: can be drawn into wire : can be drawn into wire

conduct heat and electricity well conduct heat and electricity well lustrouslustrous

Properties of Metals - MicroProperties of Metals - Micro Appear different colors when metals Appear different colors when metals

are in tiny clusters (nanoparticles)– are in tiny clusters (nanoparticles)– up to 30 atomsup to 30 atoms

Stained glassStained glass Lycurgus cupLycurgus cup

How Small is a How Small is a Nanoparticle?Nanoparticle?

NanoNano 1 billionth of a 1 billionth of a

metermeter

Properties of Nonmetals

• Not Malleable or ductile – brittle

• Poor conductors of electricity

• dull

Properties of Metalloids

• Properties of metals and nonmetals