WORD Technology
Chemistry Matter Volume Mass $eight 'rop roperties )tructure *aws *aws(( 'rin 'rinci cipl ples es
TERMS DEFINITION Application of science science to improve the quality of life The branch of science that deals with matter, its properties, changes ,composition and laws or principles governing the changes Anything th that oc occupies sp space an and h ha as m ma ass Other word for space Amount of matter present in an object !g, g, mg, lb, o"# %ravitational pull acting on an object &, dyne# Charac racteristics( qu qualities Arrangement of matter +pla +plana nati tion on to to the the chan change ges s
IMPORTANCE OF CHEMISTRY $e need to study Chemistry because we and the environment are matter ant to • familiari"e the matter around us
BRANCH OF CHEMISTRY -iochemistry Anal Analyt ytic ical al Chem Chemis istr try y Organic Ch Chemistry .nor .norga gani nic c Che Chemi mist stry ry
'hysical Chemistry %eneral Chemistry
BRANCHES OF CHEMISTRY DEFINITION )tudy of of organic compounds where humans are made of Anal Analys ysis is of the the com compo posi siti tion on of of sub subst stan ance ces( s( mate materi rial als s )tudy of of ca carbon an and it its compounds )tud )tudy y of of non non carbo arbon n co contai ntaini ning ng comp compo ounds unds /eal /eals s with with the the ener energy gy chan change ges s happ happen enin ing g in chem chemic ical al reactions -asic concepts of chemistry STATES OF MATTER
Molecules are compress Molecules are slightly apart
)olid *iquid %as
Molecules are far from each other
'lasma
A form of gas
-ose3+nstein Condensate
A form of liquid
/efinite volume 1ied volume /on2t have fied volume
SCIENTIFIC METHOD )ystematic way of finding answers in a problem • STEPS 45 6now 6now the the prob proble lem m 75 Ma!i Ma!ing ng obs obser erva vati tion on 85 Ma!i Ma!ing ng hypo hypoth thes esis is 95 Test Test the hypothe hypothesis sis throu through gh eperim eperiment entati ation on :5 Anal Analy" y"e e the the data data gat gathe here red d ;5 Ma!e Ma!e a con concl clus usio ion n SCIENTIFIC ATTITUDES ATTITUDES
0as definite shape Only occupies the shape of the container Composed of energy charged particles 'roduced only in a temperature near absolute "ero /on2t have fied shape
45 75 85 95 :5 ;5 =5 >5
6een 6een obs obser erve ver( r( Cur Curio iosi sity ty Open Open3m 3min indn dnes ess( s( Objec Objecti tivi vity ty
PROPERTY
Chemical 'roperties
'hysical 'roperties
DEFINITION Can Can be obse observ rved ed(( meas measure ured d only only after a matter underwent a change in composition
Can Can be obse observ rved ed(( meas measur ured ed even even with withou outt the the matt matter er unde underg rgoi oing ng a change in composition
• • •
EXAMPLE combustibility chemical reactivity rusting formation
•
: senses
TYPES OF PHYSICAL PROPERTIES
+tensive( etrinsic
'roperties that depend on the amount of matter present
.ntensive( intrinsic
'roperties that depend on the !ind of matter present
• • • • • • •
Mass Volume Taste Odor /ensity -oiling point +lasticity
CHANGES IN MATTER CHANGE
DEFINITION
'hysical Change
Changes that do not alter the composition of substance
Chemical Change
Changes in the composition of substances to form a new substance
Melting
)olid to liquid
+vaporation
*iquid to gas
)ublimation
)olid to gas
1ree"ing
*iquid to solid solidification#
Condensation /eposition
%as to solid
• • • • • • • •
PHASE CHANGES Melting of snow and ice +vaporation of water or refrigerant )ublimation of dry ice, free3drying of coffee 1ree"ing of water or a liquid metal 1ormation of dew 1ormation of frost and snow
EXAMPLE -rea!ing Melting 1ree"ing %rinding
0eat is absorbed by the matter
0eat is released by the matter
CLASSIFICATION CLASSIFICATION OF MATTER Classified according to composition# •
'ure substance A matter that is composed of only one !ind of particle o KINDS OF PARTICLES o Atoms o Molecules .ons o KINDS OF PURE SUBSTANCES +lements ? 'eriodic Table o )implest form of matter Made up of only one !ind of atom or molecule
M+TA*) @sually hard and solid ecept 0g, which is a liquid5 Cs and
KINDS OF ELEMENTS &O&M+TA*) )ome are solid, liquid bromine#, or gas5 @sually soft
M+TA**O./) )olids
%a melt in unprotected hand Malleable and ductile Conductor of heat and electricity *ustrous and shiny 0igh density 0igh melting and boiling points 0igh tensile strength
o
ecept diamond -rittle -asically insulators /ull ecept diamond *ow density *ow melting and boiling points *ow tensile strength
-rittle .ntermediate electrical conductivity .ntermediate reflectance .ntermediate density *ow melting and boiling points *ow tensile strength
Compounds 1ormed when 7 or more elements combined chemically in fied proportions
CLASSIFICATION CLASSIFICATION OF COMPOUNDS According to Composition
•
Organic ? C;047O; , C09 with carbon o
•
.norganic ? &aCl , 07O , 07 , )O9 without carbon o According to Chemical -ond .onic ? M &M , +&aC. • o .onic bond is present
• •
Covalent ? &M &M , 07O o Covalent bond is present
Miture o
Composed of 7 or more substances that combined physically in variable proportions
CLASSIFICATION CLASSIFICATION OF MIXTURE According to number of phases# 0omogenous( )olutions ? sea water, air o )ingle3phased mitures All the parts are identical 0eterogeneous ? )alad, soup, garbage o Mitures consisting of 7 or more phases $ith parts that are dissimilar KINDS OF HETEROGENEOUS )uspension • The suspended particles can be seen seen and are large to be trapped in a filter Colloid Miture with particles bigger than the particles of a solution but • smaller than those of a suspension Coarse Miture • The particles can be separated separated mechanically • -rownian Movement
• • • •
DIFFERENCE BETWEEN COMPOUND AND MIXTURE COMPOUND MIXTURE 1ied proportion Variable proportion • Cant be separated by ordinary Cant be separated by ordinary • physical means physical means • Chemically combined 'hysically combined • Can be epressed in formulas Cant be epress in formulas
METHODS OF SEPARATING MIXTURES •
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•
•
• •
•
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1iltration o The pouring of the miture through a piece of paper filter paper# which lets the liquid filtrate# pass through but catches the solid residue# 1lotation The removal of suspended particles particles either by sedimentation or coagulation coagulation o @sed in mining to separate precious metals( minerals from impurities o /istillation Ma!es use of the differences in boiling points evaporation and condensation#5 o The gas is then condensed bac! to a liquid distillate# /ecantation The pouring of the liquid from a miture to separate the liquid decante# from o the solid particles Crystalli"ation o Occurs when simple sea water is allowed to evaporate Centrifugation The settling of tiny suspended particles using a centrifuge5 Tis hastens the o settling of the precipitate in a suspension5 Centrifugate centrifugation • The liquid that comes from centrifugation Chromatography A solution ca nbe separated by allowing it to flow along a stationary substance o o @ses the different degrees of adsorption of the components to a stationary substance KINDS OF CHROMATOGRAPH CHROMATOGRAPHY Y 'aper Chromatography Column Chromatography Magnetism o @sed to separate a metal from a non metal Mechanical )pearation @se machines to separate mitures o
EVIDENCE OF CHEMICAL CHANGE 45 Chan Change ge in in colo color, r, tast taste, e, odo odorr 75 form format atio ion n of a new new sub subst stan ance ce 85 evol evolut utio ion n of gas gas 95 prod produc ucti tion on of of heat heat and and lig light ht :5 form format atio ion n of pre preci cipi pita tate te ;5 produc productio tion n of sound sound and and mechan mechanica icall energy energy ENERGY • capacity to do wor! or to transfer heat POTENTIAL ENERGY • the energy stored in an object because of its position or composition KINETIC ENERGY • energy in motion
• • • • • • • •
LAVOISIER, ANTOINE LAURENT (1743-174! B1ather of Modern Chemistry chemist, politician, lawyer, farmer, ban!er born in 'aris, 1rance on August 7;, 4=98, son of a wealthy lawyer suited law, also attended lectures on scientific studies in 4==4, married Marie 'aul"e acted as secretary and made many drawings for his boo!# they had no children member of Bfarm %eneral collect taes for the !ing# during 1rench , 4=E9, *avoisier was beheaded guillotine#
IMPORTANT CONTRIBUTIONS CONTRIBUTIONS Oygen Theory of -urning 'hlogiston Theory of -urning# • o Accepted eplanation of burning
• • •
1ound out that water is composed of 7 gases O7,07# +plained the respiration process the body uses breathened oygen to burn food, which gives the body its heat# $or!ed with other chemists to set up a system of naming chemicals
IMPORTANT "UALITIES
• • • •
•
*avoisier didn2t ma!e any discoveries of his own but he gave correct eplanations to the discoveries of others 0e insisted on eact measurements in all his eperiments 0e helped introduce methods of eactness in chemistry 0e would accept no idea unless it could be proved LAWS OF CHEMICAL COMBINATION *aw of Conservation of Mass The total mass in any chemical chemical or physical change does not change5 change5 o The number of substances may change, the properties may change, but the o total amount of matter remains constant5 1e ) 1e) F 4G g# :g# 4:g#
•
*aw of /efinite Composition 1ormulated by Hoseph 'roust 4=:9 ? 4>7;#, a 1rench chemist o +lements combine to form compounds in definite proportions by mass o 07 O F 70I4O 4 4 54 4J >>5>EJ
•
*aw of Multiple 'roportions $hen 7 elements combined to form 7 or more compounds, the masses of one o element that combined with a fied mass of the elements are in a ratio of small whole numbers C O 4st co compound 8 5G G g : 5 GGg 7nd compound ; 5G G g 4G5GGg
F
Mass of O 4 st compound# Mass of O 7nd co c ompound#
F
:5GGg 4G5GGg
F
K or 4I7
DEVELOPMENT OF THE ANATOMIC THEORY •
•
*eucippus teacher# and /emocritus student# -elieved that the atoms were invisible, indestructible, and the smallest particle o of matter called Batomos5 0e believed that these atoms differ in shape, shape, si"e, si"e, weight, weight, sequence, sequence, and o position Aristotle
•
Hohn /alton 4=;;34>99# An +nglish chemist and physicist o )tat )tated ed that that his his atom atomic ic theo theory ry base based d on appr appro oim imat atel ely y 4:G 4:G year years s of o investigation by scientists such as
•
$illiam Croo!es 4>873 4E4E# )tudied matter using a powerful vacuum pump called the BCroo!es2 Tube o /iscovered the Bcathode Bcathode rays by connecting the tube to an eternal source source of o electricity and noticing that a flash of light or ray coming from the negative electrode cathode# and moving to the positive electrode anode#
•
Hoseph Hohn Thomson %ave the name of Belectron to the cathode rays o /iscoverer of the electrons o @sed magnetic and electric fields to measure the value of the ratio of the o electron charge to its mass
+ M o o
•
F
45=:E 4G>
coulomb( gram
1ound out that hydrogen is the lightest atom with its mass of 4(4>9G 'ropos 'roposed ed a model model of an atom as a positi positivel vely y charge charged d sphere sphere where where the elect electron rons s are embedd embedded5 ed5 This This model model is calle called d the Braisi Braisin n ca!e ca!e model model or Bwatermelon model where the raisins or seeds are the electrons
;>3 4E:8# o Measured the charge of the electron with the use of his oil3drop eperiment + F 345;G7 4G34E coulomb o
And later the results of Thomson and Milli!an, the calculation of the mass of an electron +# 345;G7 4G34E c M# 345=:E 4G>c(g M F E544 4G37>g F mass of a negative electron
•
+ugen %oldstein o /iscovered the canal rays 'article that were left out of the atoms or molecules after electrons had been pulled out
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$ilhel 'rentgen 49:3 4E78# /iscovered that highly energetic rays could penetrate matter and later called o these BL3rays
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0enri -ecquerel 4>:73 4EG># o Associated L3rays with fluorescent materials by using a used uranium ore /iscovered radioactivity uranium# o Any material such as uranium that spontaneously emits radiation said to radioactive
•
+rnest
SYMBOL
NATURE
CHARGE
a N
0elium nuclei +lectron
7 34 G
PENETRATIN G POWER 4 4 GG 4G,GGG
'erformed the alpha3scattering ecept to test the raisin bread o RESULTS OF THE ALPHA-SCATTERING EXPERIMENT Most of the gamma particles passed through undeflected empty space • The atom is mostly an empty
o
o
A few passed through with large angles of deflection • %amma particles hit the side of the tiny solid part in the atom A few gamma particles bounced bac! • They had a Bhead on collision with the tiny solid part of the atom
proposed that most of the mass and positively charged parts of the atom, the protons, must be concentrated in a small region called the nucleus Thought that the electrons are distributed in the space outside the nucleus of the atom
•
Hames Chadwic! 4>=43 4E=9# Atoms Atoms of the same elemen elementt that that have have the same atomic atomic number number but with o different atomic mass
•
.saac &ewton A scientist that wor!s on light o -elieved that the light was made of Bcorpuscles or particles, although a later o theory held that light was made of waves
ISOTOPES • atoms that have the same number of protons but different number of neutrons
ATOMIC NUMBER ($! • gives the number of protons or electrons in an atom • .t is shown by the subscript ATOMIC MASS (A! gives the sum of the number of protons and neutrons in an atom • it is shown by the superscript • EXAMPLES
A5 &+@T +@TG 8:
/A*T /A *TO& O& MO/+ MO/+* * T0OM)O& MO/+* &@C*+A< MO/+* -O0< MO/+*
Al
'rotons I 48 +lectrons I 48 &eutrons I 49
As
'rotons I 88 +lectrons I 88 &eutrons I 97
Mg -r
7
34
'rotons I 47 +lectrons I 4G &eutrons I 47 'rotons I 8: +lectrons I 8; &eutrons I 9:
EARLY MODELS OF AN ATOM Atom Atoms s are sol solid id inde indest stru ruct ctib ible le sphe sphere res s
-O0<3 )@MM+<1+*/ MO/+*
+lectrons in elliptical orbit
@A&T@M M+C0A&.CA* MO/+*
)chrodinger proposed a wave equation from which atomic orbitals are derived5 .t is concerned w( the probability of finding a given electron in the space outside the nucleus +cited state3transfer to higher energy level %round state3lowest possible state +nergy absorbed +nergy released3light
"UANTUM NUMBERS numbers used to describe the probable locations of the electron • PRINCIPAL "UANTUM NUMBERS • Tells the number of main energy level where where e3 can be found n F 4,7,8,9P o o if n F 4 34st energy level o
nF7 37nd energy level
o
nF8 ? 8rd energy levelP55
A$IMUTHAL "UANTUM NUMBERS defines the shape of the orbital • tells the !ind of sublevel occupied by the e3 • l F G ? s o o l F 4 ? p o lF7?d l F8 3 f o MAGNETIC "UANTUM NUMBERS • /escribes the orientation of orbitals in space • Tells the number of orbitals occupied occupied by the e3 o ml F 34 → G → l o
l F G → ml FG →4 orbital → 7e3 → s
o
l F 4 → ml F 34 G 4 →8 orbital → ;e3 → p
o
l F 7 → ml F 37 34 G 4 7 →: orbital → 4Ge3 → d
o
l F 8 → ml F 38 37 34 G 4 7 8 →= orbital → 49e3 → f
SPIN "UANTUM NUMBERS tells how the e3 spin in their aes as they revolve around the nucleus • cloc!wise3 M sF 34(7 o o
countercloc!wise countercloc!wise ? Ms F 4(7
ELECTRON CONFIGURATION CONFIGURATION arrangement of electrons in an atom • RULES TO BE FOLLOWED 45 Aufb Aufbau au 'rin 'rinci cipl ple e e3 occupy the orbitals in order of increasing energy level 75 'auli2 'auli2s s +clus +clusion ion 'rinci 'rinciple ple
85
7 e3 occupying the same orbital should have opposite spins ↑↓ 0und2s
>e3 → ↑↓ ↑↓ ↑↓ ↑ ↑ F d sublevel THE MODERN PERIODIC TABLE • periods(series hori"ontal rows o = periods(series o groups(families • vertical columns o o 4> groups(families A3> groups(families representative elements# .A ? Al!ali metals • ..A ? Al!aline +arth Metals • ...A ? -oron group • .VA ? Carbon group • VA ? &itrogen group • V.A ? Oygen group • V..A ? 0alogen group • V...A ? &oble gases( .nert gases • -3 4G groups(families transition metals(elements# VALENCE ELECTRON electron in the outer most main energy level • DETERMINING THE PERIOD AND FAMILY ON AN ELEMENT
•
44
•
77
&a ? 4s7 7s7 7p: 8s4 nF8 o val e3 F 4 o periodF8 o familyF.A o
Ti Ti ? 4s7 7s7 7p; 8s7 8p; 9s7 8d7 nF9 o o val e3 F 7 o period F 9 o family F .V-
DETERMINING ATOMIC NUMBER
4A 7A 8A 9A
ns4 ns7 ns7n p 4
ns7n p 7
ns7n p
:A
8 7
ns n p
;A
9
ns7n p
=A
: 7
ns n p
>A
;
ns4md
4-
4G 7
ns md
7-
4G
ns7md
8-
4 7
ns md
9-
7 7
ns md
:-
8
ns7md
;-
9 7
ns md
=-
:
ns7md ; 7
ns md
>-
= 7
ns md >
• •
period38 1amily38A 4s7 7s7 7p; 8s7 8p4 o o Q F 48
• •
period39 1amily39A 4s7 7s7 7p; 8s7 8p; 9s7 8d4G 9p7 o Q F 87 o
PERIODIC PROPERTIES • 'roperties of an element seem to be determined largely by the electron configuration of the outermost electrons and by how far away those electrons are from the nucleus IONI$ATION ENERGY • Amount of energy needed to remove an e3 f rom atom to form # ions • .oni"ation when an atom loses or gains electrons to form ions o ELECTRON AFFINITY Amount of energy released when an atom or molecule molecule gains e3 forming a • 3#ion IONIC RADIUS .soelectric • o
equal numbers of electrons in identical configurations
ELECTRONEGATIVITY %eneral tendency of an atom to attract e3 toward itself • METALLIC PROPERTY • w( few valence e3 • tend to give up or donate e3 → +, .+, +A ↓A), M', .) • •
Octet rule an atom should have > valence e3 to become stable o /uet rule needs 7 valence e3 to be stable o
WAYS OF REPRESENTING AN ATOM • +lectron Configuration • @se of Orbitals • @se of Main energy level • *ewis electron dot formula consists of a chemical symbol surrounded by dots%ilbert &ewton *ewis# o • Chemical symbol represents the nucleus and inner e3 o /ots • o represents the valence e3 of the atom
