phy chem 1-6

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Prepared by Ragaventhan www.studysmart.page.tl

1.MATTER

Proton no (no. of protons): no. of protons in the nucleus

of an atom

Proton no. = no. -Nucleon no. : no. protons & neutrons in the nucleus

Isotopes: atoms of the same element that contains same

proton no. butnucleon no.

Have = chemical properties Havephysical properties

Where, : nucleon no. of isotopes 1, 2,3x, y, z : relative abundance

Atomnucleon

proton

neutronelectrons

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Interpret mass spectra in terms of molecular fragments

Molecular ion (x %) usually has highest m/e mass = RMM of the compound Where , : m/e

x, y, z : relative abundance/height

formulas

solution that diluted with water

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THE GASEOUS STATE

Boyles law Charles law

(final)

-gas that obeys ideal gas

-real gases obeys at ( )

Avogadro Law

equal V of all gases at (=T/p) have equal no. ofmolecules

T = 0 (273K) & p = 1 atm ()

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Ideal gas equation

Gas that obeys the eq. ideal gas/perfect gas

(at fixed mass of g)

When

R 8.31Jk-1

mol-1

0.082dm3atmK

-1mol-1

p Pa/Nm-2

atm

V m3

dm3

T K K

Daltons law

Mole fraction of A,

Partial pressure, (mole fraction)Deviation from ideal behavior

Conditions: a. V occupied by molecule - negligibleb. f.a. between molecules

idealpV=constant

realpVconstantReal gases obey / p, Tdeviate from

ideal gas behavior

p, T

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A.Negative deviation1. intermolecular f.a. between mol.

- > compresssible- V of gas

2. polar bonds weak i.f.amol. Size small

- non-polar least deviation

- polar stronger i.f.a

Marked deviation

B. Positive deviation p, V occupied by gas mol, becomes # cant be ignored V of gas 1 structural form(under = p/T)

Carbon

- Diamond Graphite

Structure Arranged in tetrahedral Arranged in parallel layer

Bonding

-use sp3

hybrid orbital

-c.b.

-Joined 4

-use sp2

hybrid orbital

-c.b.

-Joined 3

Properties

-harder

- MP/BP-strong c.b.

-softbond weak

- MP/BP-strong c.b.Electrical cond. - delocalized - / - / delocalized -Uses Tips of cutting Pencil lead/electrodes

Fullerenes

-spherical mol. Of 30-70 C atoms

-: buckminsterfullerene

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Sulphur

- Rhombic S Monoclinic SMol.formula S8 S8

Bond & structure Simple Simple

Colour Lemon yellow Deeper yellow

Crystalline struc. Orthorhombic latt. Monoclinic latt.

S in CS2 S IS

Phase diagram

AOSublimation curve of ice (SV)OBVapour p. curve of H2O (H2OV)OCMP curve (S H2O)slopes leftOTriple point (S, H2O, V in equi.)[.006 atm]

BCritical point> B , H2O vapour condensed to H2O

CO2 O5.1 atm L can exist p > 5.1atm MP/OC towards right -p MP

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2.ELECTRONIC STRUCTURE OF ATOMS

Energy of photons,

Emission spectrum

When an element in its gaseous state is heated at highT & p, radiation of certain are emitted.

H2 at p in discharge tube is heated. at lowest E level, ground state -absorb E jump to E level (exited state)unstable Return to E level ( stable) & emits E (photons) Quantum of E = - of E in level, E=hf Quantum hasf, contributes to 1 line to the line

spectrum

Line represent E radiated when -drops from E(unstable) to E level (stable)

Level get further from nucleus, get closer to eachother.

-between E level until it become as subs. Levelconverge.

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Ionisation E:

min E required to remove 1 mol of

from 1 mol

gaseous atoms to form 1 mol of + ions Rydberg equation

(

)

(of 1 mol H atoms)

Atomic Orbitals

Aufbau principle

--

filled from lower orbitals-4s (empty) - E level < 3d

-4s (filled) - E level > 3d

_________________ 4d

n=4 -----_________________ 4p_________________ 3d

_________________ 4s

n=3 ----- _________________ 3p

_________________ 3s

_________________ 2p

n=2 _________________ 2s

n=1 ----- _________________ 1s

Pauli exclusion principle

-max. 2 - in an orbital1s

2

Hunds rule

-fill one by one __

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3.PERIODIC TABLE

Newlands - atomic mass Period- prot. noMendeleevascending RAM Groupvalence -Moseley - prot. No.

Atomic Radii

a. Van der Waals rb. Covalent rc. Metallic r Factors affecting1. Screening effect: mutual repulsion between - in

inner shell with outer shell ( SE , AS)

2. Nuclear charge (-, attraction, NC, AS)3. Effective nuclear charge,eff=NC-SE

(:eff,AS ) / (+:eff,AS )

Properties Period GroupAtomic size NC, no.e

-,

SE (remain unchanged)-e

-added same shell

eff, attraction , AS

no. shells filled with e-,

SE > NC, eff, lesstightly, AS

Ei -NC - SE (almost =), Ei

- > Eremove e-from

1. fully occupied s orbital2. filled p orbital

AS , NC , Ei

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Electronegativity,e

-

,AS, NC, attraction 4e

-

,

AS, NC, SE,

eff

attraction 4e-

Isoelectronicatoms/ions that have = no. e-& =

electronic configuration

Ionic size

AS: + < n < -

{X

+

: = no.e

-

, -prot. no }{Y-: = no.e

-, -prot. no }

anions > cations -1 extra quantum shell filled with e-

MP/BP/Enthalpy of vaporization (Hvapour)

Giant metallic(Na-Al) Giant covalent(Si) Simple molecular(P-Ar)

-ions attracted to the

cloud of e--v.e

-, NC,

metallic b., MP/BP

-strong covalent b.

between atoms-difficult- > E, MP/BP

- weak vdWf

-mol. Size , F , - S8>P

->Ar :Diatomic > monoatomic

Electrical conductivity

Metalgood: / delocalized e-

N-metal- weak: delocalized e-/ insulator

Metalloids/semi-metal poor

Ei(NC, SE, AS)

Factors

a. ASAtomic radius , Eib. NC , e- attraction , Ei c. SE , Ei

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Periods of d-block

1. Atomic radii-almost constantENC remains constant

2. MP/BP

- strong metallic b.

- Zn/Mn : /fully filled d-shells

3. Density

- : small atomic radii, atoms tightly packed together

4. Ei- , no.protons

- > E needed to remove e- from /fully filled d-shells

Scandium(Sc) Iron(Fe)

Titanium(Ti) Cobalt(Co)

Vanadium(V) Nickel(Ni)

*Chromium(Cr) *Copper(Cu)

Manganese(Mn) Zinc(Zn)

* /fully filled d-shells > stable

Predicting group

1. (-) in 2nd & 3rd Ei = E2-E12. (-)

2/1G13/2G2

4/3G13

5/4G14 ...

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4.CHEMICAL BONDING

IONIC BOND Formed by transfer of e- from metal atom to non-

metal atom

Strong electrostatic attractionDot and cross diagram

LiF Li + F [Li]+ [ F ]MgBr2

Mg + 2[ Br ] [Mg]

+

2[ Br ]

Strength of ionic b. , S Polyatomicionic & covalent b.METALLIC BOND

: Electrostatic attraction between + charged ions & cloud

of delocalized e- v. e- freely moved particlesdelocalised no. atomic orbitals overlap large, no. of mol. orbitals

produced Conductors Semi-conductors Insulator

-v.b: v.e-, electric

free to move c.b.

- T, e. cond -E gapsmall

-Electric - e-can jump

E gap is small

-e.cond < metal, e-in

cb small

e- jump into c.b.

Good conductor T, e. cond insulator

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Semiconductor

Doping: add small amount of the subs. e.cond Pure Siv.b(full) , c.b(empty)

Strength of metallic b. , S

COVALENT B

By sharing of e- between atoms. Electrostatic attraction between pair of shared e- Single bond - 2e- shared Bond diagram: Dot & cross d.: Strength of c.b (stronger b)

a. Shorter b , Ebb. Multiple b. >> single b.

Si

n-typeSi(4 v.e-) doped with P(5v.e-)

> e- occupy in c.b

e.cond

p-type

Si(4 v.e-) doped with gallium(3v.e-)

noe- occupy in v.be.cond

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COORDINATE B

C.b. formed when 1 atom donate 1 lone pair of e- toanother atom that has vacant valence orbital.

e-pair donoratom that has 1 lone pair of e-acceptoratom that has 1 empty orbital shell

Aspects Ionic cCovalent c

Simple Giant

Phy. app. crystalline g/l/s s

MP/BP -strong att. F> E needed 2overcome

- weak inter.F -strong att. F> E needed 2break cb.

Electrical

conductivity

Good-molten/aq

Delocalized e-

e

-

S H2O S IS IS

Org.solvent IS S IS

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Lewis structure

Shapes of molecules & ions

VSEPR theory

Lp-lp repulsion > lp-bp repulsion > bp-bp repulsion

Strongest weakest

Steps E.g

1. Count no. v. e-a. Molsimply sum upb. Polyatomic anion - + e-c. Polyatomic cation - - e-

2. Draw skeleton structurea. Single bb. Central atom(

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Geometry Molecular shape Eg.Electron pairs

bp lp Total

Linear Linear BeCl2 2 0 2

Trigonal

planar

Trigonal planarAlCl3 3 0 3

Bent/V-shapeGeCl2 2 1 3

Tetrahedral Tetrahedral4 0 4

Trigonal

pyramidal3 1 4

Bent/V-shape2 2 4

Trigonal

bipyramidal

Trigonal

bipyramidal5 0 5

See-saw

4 1 5T-shape

3 2 5

Linear2 3 5

Octahedral Octahedral6 0 6

Squarepyramidal

5 1 6

Square planar4 2 6

bondangle lone pair of e

-3 bp move closer - angle between bplp-bp e- rep > bp-bp rep

electronegativity surrounding atomcentral atom

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-Large A overlap, > cb

-.b > .bsideways overlappingHYBRIDISATION

Mixing together 2/> atomic orbitals (=E)

Orbitals sp3

sp2

sp

Diagram

Ground

state

Exited state

hybridised

state

E.g.

Hybridization of S & P orbitals in the N/O atom

ELECTRONEGATIVITY-Ability of an atom that is covalently bonded to another

atom to attract e-to itself

en- across period/ down group

Bo

nds

Non-polar

2 identical atom

bonding e- shared equally between2 atoms & attracted equally

diatomic mol (Cl2) : = en-Polar

2 atoms identical

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Polarisation: separation of charge in a polar covalent

bond

-2 electrical charges of opposite signs are separated bysmall distance

po on n Molecular shape

IONIC CHARACTER IN COVALENT COMPOUND

Polar c. mol. has ionic character : presence of dipoles polar, ionic character

1.7 Ionic0.4-1.7 Polar c0 Non-polar c

COVALENT CHARACTER IN IONIC COMPOUND

To incomplete transfer of e- > degree of polarization of anion, > amount of

covalent character. Cation : polarising power

n on Anion & on pp

- pp nv on on z

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INTERMOLECULAR F

VAN DER WAALS Fa. Permanent dipole F

- Exist between polar molecule- + end of dipole of 1 mol. will attractend of

another mol.

- d-d F/permanent d-permanent d F- , >polar, strength of d-d attraction, BP

b. Temporary dipoleinduced dipole F- Temporary fluctuations in e- density in a mol.

Strength

a. Molecular sizebigger size, vdWF stronger, BP b. TSAlarger SA, greater contact with mol, F, BP

i. = no. C atoms, - structural formula, - BPii. Isomerstraight chainlarger SA

-branched chainsmaller SAc. RMM td-id F > significant than pd-pd F

- RMM, attraction

- almost similar - d-d F > significant- > polar mol, stronger att.

Effect of going down

a. G17,G18atomic size , F, BPb. Homologous series, mol.size, id, BPAlkenes series ,BP , enthalphyof vap.

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HYDROGEN BOND

d-d attraction between H atom covalently bonded toO,N,F & an unshared pair of e

-on neighbouring en atom.

a. H is covalently bonded - en- atoms (FON)b. unshared pair of e-/another en- atom

vdWF < Hb. < Cb.

x lp x H.b.

Effect

1. HF is strong2. BP of hydride (G14-G17):RMM, mol.size, F,

BP

3. Sol. In organic compound in H2O4. Dismerisation in carboxylic acid5. H.b. in ice & H2OMol. H. Bond

a. Intermol-between 2 - mol

b. Intramol-between same mol.

Ionic compound dissolve inH2O

-cation + (-) end of H2O-anion + (+) end of H2O Ion dipole F

Ions involved?

Polar moleculesinvolved?

Td-Id FH atoms bondedto F/O/N atoms

H b. d-d F

Mol & ions bothinvolved?

Ionic bIon-d F

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5. REACTION KINETICSRATE OF REACTION

[]

Determine ROR quantity of gas/conc./time taken

COLLISION THEORY

Eff.coll: coll of react mol that will results chem react. Ea: min E of reactant mol. must acquire for chem.

Reaction occur.

Energy profile diagram:

Reaction occur when reactant part. Must collide

possess min Ek(Ea)

have right orientation during collision

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Factors that affect ROR: SA/conc./T/catalyst Conc., > reactant particles/V, > collisions, f.coll,

f.EC ROR

RATE LAW

[] [] [][]where k: rate constant at constant T

m/n: rate order with respect to reactant A/Bm + n : overall reaction order

AspectsORDER OF REACTION

0 1st

2nd

Rate = k [A]0

= k = k [A]1

=k[A]1[B]

1=k[A]

2

Unit for k mol dm-3

s-1

s-1

dm3mol

-1s

-1

Graph of ratevs [A]

Integration of

rate equation[] [] n[] n[]

[]

[]

Graph

Half time,t1/2 [] Not constant

Constant t2 = t1

[] Not constant t2 = 2t1

Notes Rate conc. ROR conc. ROR conc.Graph

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Calculation method

[][][] [][][] [][][]

[][]

()

o o ()

Graphical method

Rate = k [A]n []

Reaction mechanisms

Overall equation: 3A + B + C D + FArrhenius equation, n n

n

Experiment [A] [B] [C] Initial rate

1 x1 y1 z1 r12 x2 y1 z1 r2

3 x1 y2 z2 r3

T Ea f f, ROR

T Ea k , ROR

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CATALYST

: substances that alters the ROR without chemically

changed.

CATALYSIS

Homogenous c.

- tansition metal ion

-catalyst + R exists at + phase

Heterogenous c.

-transition element

- catalyst & R exist at - phase

a. adsorption of R at S of catalyst

b. reaction (R+C)

c. desorption of prod. at S of catalyst

Autocatalysis

-product = catalyst

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