Allen Chemistry Handbook for JEE/NEET [1, 2017 ed.]

Table of contents :
1. Physical Chemistry
2. Organic Chemistry
3. Inorganic Chemistry

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Serial No. 1. 2. 3. 4. 5. 6. 7. 8. 9.

CONTENTS PHYSICAL CHEMISTRY

Page No.

Chemical Kinetics Nuclear Chemistry Thermodynamics Thermochemistry Chemical Equilibrium Ionic Equilibrium Electrochemistry Liquid Solution Solid State

1 5 6 12 14 18 25 30 34

10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29.

Alkane Alkene Alkyne Alkyl halide Comparision SN1 & SN2, E1 & E2 Alcohol Ether Carbonyl compounds Grignard Reagent Carboxylic acid Est er Amide Amine Benzene Organic Reagent Organic Name Reaction Addition Polymers Condensation Polymers Carbohydrates Amino acids & Proteins

38 39 41 42 44 45 48 49 50 51 52 55 56 59 60 67 71 72 73 75

30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41.

Alkali Metal Alkaline Earth Metals Boron Family Carbon Family Nitrogen Family Oxygen Family Halogen Family Nobel Gas Metallurgy Coordination Chemistry d-Block Salt Analysis

ORGANIC CHEMISTRY

INORGANIC CHEMISTRY

76 79 82 85 87 89 91 92 93 97 100 102

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Rate of reaction (ROR) =

Rate of disappearance of reactant (appearance of products) Stoichiometric coefficient of reac tant (products)

For a reaction : aA + bB

cC + dD 1 d[A] a dt

Instantaneous rate :

1 d[B] b dt

1 d[C] c dt

1 d[D] d dt

[C] t

[D] d t

Relationship between rate of reaction and rate of disappearence of reactant (rate of appearance of product).

Average rate :

1 a

[A ] t

1 b

[B] t

([P]2 t2

[P]1 ) t1

Graphical method for determining rate :

Avg. Rate =

[R]2 t2

[R]1 t1

Instantaneous rate = –

OA OB

= +

1 c

1 d

OA = ± slope of tangent OB

Important kinetic expression for reaction of type A Order

Zero

1st

Differential

Rate = k

Rate= k[A]

Integrated

[A 0 ]–[A]= kt

kt = In

rate law

rate law

[A ]0 = 2k

Half life (t1/2)

t 1/2

(t 3/4)

t 3/4 =1.5 t 1/2

t 1/2

[A]0 [A]

ln 2 = k

t 3/4 = 2 t 1/2

1

B :

2nd

Rate = k[A] 1 kt = [A ]

t 1/2

2

1 [A ]0

1 = [A ] k 0

t 3/4 = 3 t 1/2

nth

Rate = k[A] n

kt =

1 1 (n 1) [A ]n

t 1/2

1 2n 1 1 = k (n 1) [A ] n 1 0

1

1 [A]n0

t 3/4 = (2 n–1 + 1) t 1/2

1

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Graphs of various order Order

Rate vs [A]

[A] vs t

log [A] vs t

1 vs t [A ]

Zero order

First order

Second order Where [A]0 [A] t1/2 t3/4

initial concentration concentration at time t time taken for initial concentration of reactant to finish by 50%

time taken for initial concentration of reactant to finish by 75%

Monitoring Kinetics Experimently :

e.g.

The kinetics of reaction can be followed (i.e. order, rate constant etc. can be established) by measuring a property which changes with time. (i) Total pressure in a gaseous reaction. (ii) Volume of a reagent (Acidic, Basic, oxidising or reducing agent) (iii) Volume of a gaseous mixture (V) (iv) Optical rotation (R) For a Reaction An nB t = 0 c 0 c0 conc. at t = 0 t = t c–x nx ct conc. at t = t t= 0 nc c conc. at t = For any measurable property X proportional to the concentration of reaction mixture at various times, following relations can be expressed. In terms of (i) X0 and x (ii) X0 and Xt (iii) X and Xt (iv) X0, Xt, and X 1 X0 k = t ln X x 0

k=

1 (n 1) X 0 ln t nX 0 X t

1 (n 1) X k = ln t n(X X t )

where x amount of reactant reacted in time 't'. X0 measured property at t = 0 Xt measured property at t = t X measured property at t = 2

1 X k = ln t X

X0 Xt

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(i)

Examples : (For Monitoring Kinetics Experimently) Inversion of cane sugar : H C12H22O11 (aq) + H2O C6H12O6(aq) + C6H12O6(aq) Sucrose dextro-rotatory

Glucose dextro-rotatory

(+66.5°)

r0 = rt = r = (ii)

k

Fructose laevo-rotatory

(+52.5°)

r 2.303 log t r

(–92°)

(Laevo-rotatory)

r0 rt

rotation at time, t = 0 rotation at time, t = t rotation at time, t = Acidic hydrolysis of ethyl acetate : CH3COOC2H5 + H2O k

2.303 V log t V

H

V0 Vt

CH3COOH + C2H5OH

V0 = Volume of NaOH solution used at time, t = 0

Vt = Volume of NaOH solution used at time, t = t V = Volume of NaOH solution used at time, t =

Note : Here NaOH acts as a reagent. Acetic acid is one of the product the amount of which can be found by titration against standard NaOH solution. But being an acid-catalysed reaction, the acid present originally as catalyst, also reacts with NaOH solution. Important characteristics of first order reaction : t1/2 is independent of initial concentration.

In equal time interval, reactions finishes by equal fraction.

t = 0 t = t t = 2t 2 Reactant conc. a0 a 0x a 0x x = fraction by which reaction complete in time 't'. Graph of ln[A] vs t is straight line with slope = Graph of [A] vs t is exponentially decreasing.

• • •

– – –

t = 3t .... 3 a 0 x ........

k 2.303

Zero order :

t1/2 of zero order is directly proportional to initial concentration. In equal time interval, reaction finishes by equal amount. t = 0 t = t t = 2t t = 3t ..... C0 C0 – x C0 – 2x C0 – 3x .... Graph of [A] vs t is straight line. A zero order reaction finishes in t

Temperature dependence :

[A ]0 k

Arrhenious equation : k = A.e–Ea/RT E a = minimum energy over and above the avg. energy of reactant which must be possesed by reacting molecule for collision to be succesful. A = frequency factor - proportional to number of collisions per unit volume per second. 3

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– –

e = Fraction of collision in which energy is greater than Ea. A and Ea are constant i.e. do not vary with temperature –Ea/RT

Ea RT Graph : Graphical determination of Ea. ln k = ln A –

Temperature coefficient = By default T = 298 K

k T 10 kT

Variation of rate constant with temparture

ln

Endothermic and exothermic reactions :

k2 k1

H = E af – E ab Parallel reaction : (i)

Rate = (k1 + k2 ) [A] - (differential rate law)

(iii)

t1/2 =

(iv)

% of B =

(ii)

(v)

k1 k2

[B ] [C ]

0 .6 9 3 k1 k2 k1

k1

[A] = [A]0 e –(k 1

k2

k2 )t

100 ; % of C =

k1

k2

k2

100

Pseudo-order reaction :

Rate law rate = k [A]m [B]n Pseudo rate law : rate = k1 [A]m [B] assumed constant in two cases : (i) B in large excess (ii) B CATALYST 4

Ea 1 R T1

1 T2

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NUCLEAR CHEMISTRY

All nuclear reactions are first order : Two types of nuclear reaction :

First order

t = 2.303 log

N0 Nt

N0

dN t = dt

Activity = A t =

A t = Rate of decay

decay =

A Z X

To A Z

A 4 Z 2

t1

Decay constant Initial nuclei

Nt

Nuclei at 't'

N t ; Nuclei/sec.

ln 2

2

Y

( a ) Artifical radioactivity (b) Radioactivity (spont.)

Particles at high velocity

4 2 He

size of large nuclei

decay = 01 e at high velocity

X

# To

A Z+1

P + –1/ e

n ratio. P

# Nuclear change in 1 0

n

1 1

P

0 1

e

decay

-decay : Photons from excited nuclei after No effect on n/p ratio High energy e/m radiation. Mean life , tavg =

– or

– decay

1

Parallel decay : t = 0 N0 t = t N 0 –x–y eff. = 1 + 2 1 1 1 = + t eff. (t 1/2 )1 (t1/2 )2

No dependence on temp. 5

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THERMODYNAMICS THERMODYNAMICS :

Study of heat and work interaction between system and surrounding.

A macroscopic science.

Thermodynamic laws are experimentally verified.

Important terms and concepts in thermodynamics. System - Portion of universe under investigation. Surrounding - Anything apart from system.

Boundary - Real or hypothetical line or surface between system and surrounding. Wall - A real boundary.

Rigid wall - Immovable wall (w = 0) Non-rigid wall - Movable wall (w Adiabatic wall - Insulated wall (q

0)

0)

Diathermic wall - Non-insulated wall (q

0)

State variable - Variable which defines state of system.

State of system - A condition defined by fixed value of state variables.

State of thermodynamic equilibrium - A condition in which state variables do not vary with time.

Extensive state variable : State variable whose value depends upon size of system. Examples - mass, volume, charge, mole etc.

Intensive state variable : State variable whose value does not depends upon size of system. Examples - concentration, density, temperature etc. Path variable :

Heat : Mode of energy transfer between system and surrounding due to temperature difference.

Work : Mode of energy transfer bet ween system and surrounding due to difference in generalized force.(Net force).

(i)

(ii)

(iii)

(iv)

THE FIRST LAW

Energy of universe is conserved

Internal energy (U) of a system is state function. U=q+w

U = Increase in internal energy of system. q = Heat absorbed by the system w = work done on the system In a cyclic process

Cyclic

U=0

If a cyclic process involves n steps with heat absorbed and work done on the system, q i and w i respectively, then Cyclic

U

i n i 1

qi

wi

i n i 1

qi

i n i 1

wi

0

Qnet = – Wnet (in a cyclic process)

6

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(v)

If two states 1 and 2 are connected by n paths involving q i and w i, heat and work respectively, then

(vi)

q and w are path dependent quantities (indefinite quantities) but there sum is a definite quantity ( U).

U = q1 + w1 = q2 + w2 = .............. qn + wn

Enthalpy : A state function defined by first law H = U + PV

(i) Enthalpy is (pressure volume energy + internal energy of system) (ii) Enthalpy is also called heat content of system.

Heat absorbed at constant volume and constant pressure. qV

qp

U Heat absorbed by a system in isochoric process is equal to change in internal energy of system.

H Heat absorbed at constant pressure by a system is equal to change in enthalpy.

Enthalpy change :

For General process H =

U + P2V2 – P1V1

...........(i)

H =

U + P V

..........(ii)

H =

U + V( P)

.........(iii)

For Isobaric change -

For Isochoric change For a differential change

dH = dU + PdV + VdP

.........(iv)

Ideal gas processes : (See table page no. 11) Enthalpy of phase transition

H va p = heat absorbed at constant temperature and pressure to convert one mole liquid into it's vapours. = molar enthalpy of vapourisation.

Hfusion= heat absorbed at constant temperature and pressure to convert one mole solid into liquid. = molar enthalpy of fusion.

Hsublimation = heat absorbed at constant temperature and pressure to convert one mole solid into it's vapours. = molar enthalpy of sublimation. H

=

U + P(V f – V i) since phase transtions are isobaric and isothermal processes.

Relationship between For vapourisation For sublimation

For fusion

H vap =

H and

Uvap + RT

Hsublimation =

Hfusion

U for phase transtions.

U fusion

Usublimation + RT

Heating curve at constant pressure : (Reversible, isobaric vapourisation at boiling point.) (Reversible, isobaric, melting at melting point.)

7

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Enthalpy of reaction ( r H) :

The enthalpy of reaction is heat exchanged at constant pressure and

temperature to convert the stoichiometric amount of reactant into product with specified physical state according to balanced chemical reaction at constant temperature and pressure. for aA + bB r r

cC + dD

H = q P = enthalpy of reaction

H = (cH C + dH D – aH A – bH B ) where H A, H B , H C, H D are molar enthalpies of A,B,C and D.

Relationship between r r

H =

H =

r r

U +

n g RT

H and

r

U

r

U + P(V f – V i )

(for ideal gas)

(for non ideal conditions)

The stoichiometric coefficient of solids and liquids in not considered in calculation of (because VS ~ VL 0

( G)T,P % 0 Change in

Process spontaneous

G for phase transition :

For reversible phase transitions :

For irreversible phase transition : Change in

r r

GP,T =

G for chemical reaction :

aA + bB

r

G = 0.

HP,T – T SP,T

cC + dD

G = cGC + dG D –aGA – bGB

G =

G =

Where, Q

r r

.....(i)

H – T rS

.....(ii)

G° + RT ln Q

.....(iii)

Reaction quotient

9

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G / G° and state of chemical equilibrium :

•

•

•

At equilibrium : G = 0

Gproduct = Greactant

G° = –RT ln Keq.

At equilibrium the system gibb's function is at minimum value. Difference between r r

G and

r

G° :

r

G = change in Gibb's function when all the reactants and products have arbitrary activities. G° = change in Gibb's function when all the reactants and products are at unit activities.

All gases at 1 bar pressure.

All solute at molar concentration 1 M. (i)

(ii)

(iii)

Factors on which

G° depends -

r

Stoichiometric coefficients of a balanced chemical reaction. the temperature. the

r

G° is independent of actual pressure or concentration of reactants or products.

Gibb's function and non-PV work : – ( G)T,

P

= Wmax

decrease in Gibb's function at constant temperature and pressure is equal to maximum non-PV work obtainable from system reversibly. –

G = –

r

H + T rS

r

Decrease in Gibb's function = heat given out to surrounding + T rS.

10

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Process

Expression

w

Irreversible isothermal

w

Isobaric

w

nRT ln

process

nRT ln

Pext

process

w

process

Irreversible

=

w

process

V1

nRT P1

V1

0

nC V (T2

P2 V2

T1 )

P1 V1 1

nC V (T2

P2 V2

adiabatic

Polytropic process

nRT P2

= – nR T

process

adiabatic

P1 P2

Pext V2

w

for q

V2 V1

Pext V2

Isochoric

Reversible

Expression

for w

Reversible isothermal

process

IDEAL GAS PROCESSES :

P1 V1 1

w

P2 V2 n

w

R( T2 T1 ) n 1

q

nRT ln

q

nRT ln

q

V2 V1

P1 P2

Pext V2

U

H

0

0

0

V1

0

q

H

nC P T

U

nC V T

H

nCP T

q

U

nC V T

U

nC V T

H

nCP T

q

0

U

nC V T

H

nCP T

U

nC V T

H

nCP T

PV =constant

TV

TP

–1

1– /

=constant

=constant

T1 )

P1 V1 1

V2 = Final volume

&C

T2

q

T1

&1

T2 T1

R

V

n

dT

dT V1 = Initial volume

P2 = Final pressure

P1 = Final pressure

11

Work on

PV-graph

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THERMOCHEMISTRY H = q P = Heat of reaction at constant pressure

r r

E =

r

U = q V = Heat of reaction at constant volume.

r

H =

r

For mix. of reacting ideal gases at constant Temperature : U + ' ng) RT.

Exothermic Reaction : HP > HR r

H > 0

U > 0

r

Endothermic Reaction : HP < HR r

UP > U R

H < 0

r

UP < UR

U < 0

Reversible Phase Transition Isothermal and Isobaric Example :

(a) Melting or Freezing at MP

(b) Vaporisation or condensation at B.P. (c) Sublimation at sublimation point.

(d) Interconversion of allotropic forms at Transition temperature.

Sg >> S > Ss ;

Vg >> V < Vs (Water) ;

Ug >> U > Us ;

Vg >> V > Vs ;

Hg >> H > Hs ; H sub >>

At same Pressure and Temperature Hsub =

Hvap +

H vap >

Hfus.

Hfus.

For reversible phase transition. W = – Pext [ V]

H trans

S trans. =

q =

Htrans

Utrans = H =

r

Ttrans

Htrans + w

VPH (product) –

VP, VR – Stoichiometric coefficient of reactants & products G=

r

Determining (a)

(b)

(c)

VRH (Reactant)

H° =

r

H° =

r

H° =

r

VPG (product) – r

H° for reaction :- 3 methods

VP H°f (P) – VR

VRG (reactants)

VR

H°comb. (R) –

Hatomisation (R) –

VP

H°f (Element in solid state) = 0. H°f (CO2, g) =

H°f (R)

H°comb. (P)

Hatomisation (P)

H°comb. (C, grap.) 12

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H°f (H2O, ) =

H°comb. (H2, g)

aA + bB

cC + dD

;

H° = change in enthalpy when

r

a mol of A react ; r

G° =

r

H°

b mol of B react ;

VP G°f (P) –

VR G°f (R)

Gibbs enthalpy is function of P, T. P(

c mol of C formed ;

OR

r

G° =

d mol of D formed

H° – T rS°

r

G(

T(

G

H°f (H , aq) = 0 +

G°f (H+, aq) = 0 E )H | H = 0

By convention

S°m (H , aq) = 0 2

+

& ms dt = & n C dt = & C dt

q =

m

mS

=

nCm

specific

molar

heat

capacity

=

C Total

heat

heat

capacity

capacity

For strong Acid and strong base H°neutr. = – 57.1 kJ/mol.

when 1 eq. H+ (acid) reacts with 1 eq. OH– (base)

If acid or base is weak H°neut. = – 57.1 +

Hionisation

+ ve

Heat evolved in SA + SB titration = (no. of eqv. of limiting reagent) × 57.1 kJ

Resonance enthalpy = R.E. < 0 = (Energy of R.H.) – (Energy of stablest R.S.) r

H° (Actual) –

H° (theoretical) = *

r

H°hydration [CuSO4, s]

H°solution [CuSO4, s] –

VP RE (P) –

VR RE (R)

H°solution [CuSO4 5H2O, s]

Enthalpy of atomisation :

H°atomisation (O2, g) = BE (O = O) H°atomisation (C6H6, ) =

H°atomisation (Fe, s) = H°atomisation (I2, s) =

H°vap. + 3+ (C = C) +

H°sub

3+ (C – C) + 6+ (C – H)

H°sub + + (I – I) 13

+ = Bond enthalpy

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CHEMICAL EQUILIBRIUM

At equilibrium for reaction mix. properties like P, V, T, n, magnetism, colour, density become constant.

For gaseous reactions. KP = KC (RT ) KP > KC

if

KP < KC

ng

ng > 0

if

KP = KC

ng < 0

if

Units of KP = (atm )

Units of KC = (M ) Af e r H ) / RT KP = Ab

ng

ng = 0

ng

both K P & KC depend only on temperature for given reaction.

For pure solids & pure liquids (solvent) : Active mass = 1 [Kinetically]

Activity = 1 [thermodynamically] Molarity =

(i)

(ii)

Density

Molar m ass

= Constant

Reaction Quotient (QC / QP)

Used to find direction of reaction mixture – Fwd./Bwd. QC < KC or QP < KP QC > KC or QP > KP

QC = KC or QP = KP

(iii)

QP = QC (RT )

(1)

[KP >>> 1 or K C >>> 1]

(2)

[KP 0

forward

Case IV : T Increased If

r

H° < 0

If

r

backward

T decreased If

r

H° > 0

H° < 0

backward

Case V : Using Catalyst

forward

No effect on K C, KP or equilibrium concentration

Only time required to attain equilibrium is lesser. Case VI : Adding inert gas at constant V.

No effect

Case VII : Adding inert gas at constant Pressure

Same effect as Pressure decrease or volume increase Thermodynamics state of Gmix

Minimum

G r

0

/ VPGP = / VRGR If

G 14

(a)

pH Calculation of different Types of solutions : Strong acid solution :

(i)

(ii) (b)

If concentration is greater than 10 –6 M.

In this case H+ ions coming from water can be neglected,

so [H+] = normality of strong acid solution

If concentration is less than 10–6 M

In this case H+ ions coming from water cannot be neglected.

So [H+] = normality of strong acid + H+ ions coming from water in presence of this strong acid

pH of a weak acid (monoprotic) Solution :

Weak acid does not dissociated 100 % therefore we have to calculate the percentage dissociation using Ka dissociation constant of the acid. We have to use Ostwald's Dilution law (as have been derived earlier) HA

H+ +

t=0 C

teq If

C(1 – )

10–6 M, then [H 3O+] contribution from water can be ignored.

Using this [H3O+], pH of the solution can be calculated.

21

H3O+

1

+c

1

2

)

= K a2

2 )]

...... (ii)

can be calculated using equations (i) and

, [H3 O ] can be calculated as +

(c

+

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Approximation :

For diprotic acids, K a 2 V1 + V2

(2)

H solution=0

Non-Ideal solution : F < F1 & F2

......(ii)

......(iii)

Ideal and Non-Ideal solution :

Ideal solution :

......(i)

Hsolution> 0

Solution showing –ve deviation : F > F 1 & F2

VT < (V1 +V2 ) Hsolution < 0

32

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Positive deviation

DEVIATION FROM RAOULT'S LAW Negative deviation

Zero deviation

acetone + chloroform

benzene + toluene

( H=+ve)

( H=–ve)

(ii)

acetone + carbon disulphide

benzene + chlorform

(iv)

ethanol + aceton

acetone + aniline

ethanol + water

water + nitric acid

chloroform

chloroform

(i)

(iii)

(v)

(vi)

ethanol + cyclohexane

acetone + benzene

carbon tetrachloride

Azeotropic mixtures :

nitric acid + chloroform

( H=0)

n-hexane + n-heptane

ethyl bromide + ethyl iodide chlorobenzene + bromo

benzene

diethyl ether +

Some liquids on mixing form azeotropes which are binary mixture having same composition in liquid and

vapour phase and boil at a constant temperature. Azeotropic mixture cannot be separated by fractional distillation.

(i)

Types of Azeotropic mixtures

Minimum boiling Azeotropic mixtures

The mixture of two liquids whose boiling point is less than either of the two pure components. They are formed

by non-ideal solutions showing positive deviation. For example (95.5%) + water (4.5%) + water boils at

(ii)

351.15 K.

Maximum boiling Azeotropic mixtures

The mixture of two liquids whose boiling point are more than either of the two pure components. They are

formed by non-ideal solutions showing negative deviation. For example HNO3 (68%) + water (32%) mixture

boils at 393.5 K.

33

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Various type of Criptals : Characteristics Units that

occupy lattice points

Binding

forces

Some Important Characteristics of Various types of Crystals Ionic Crystals Cations and

Covalent Crystals Atoms

anions

Electrostatic

Shared

attraction

electrons

Hardness

Hard

Very hard

Brittleness

Brittle

Intermediate

between ions

Melting point Electrical

Conduction

Polar solvents

Heat of

Vaporisation

(kj mol ) –1

Heat of fusion

(kj mol ) –1

Example

Molecules

vander Waals

Graphite Low

Non-con-

Ba d

Graphite

conductor

Soluble

Insoluble

NaCl(s)

Graphite

NaCl

NaCl, KNO3

170-75

28.45

CsCl, Na 2SO 4 ZnS

Electrostatic

conductor

positively charged ions and negatively charged electrons.

Low

Varying from moderate to high Good conductors

is good

ductor in fused state

electrons.

Hard or soft

Semi cond-

crystal impe-

"sea or pond" of

Soft

Low

ductor

Positive ions in a

attraction between

Very high

uctor due to

Metallic Crystals

or Dipole-

dipole

High

rfections,conSolubility in

Molecular Crystals

Soluble as well as

insoluble

Good conductors

NH 3 (s)

Cu(s)

–

NH 3 (s)

Cu(s)

Diamond,

H2 O(s),

Na, Cu, Ag, Fe,

718-43

–

23.55

5.65

graphite,

CO 2(s),

(SiO 2), SiC

Sugar, Iodine,noble gases

Quartz

34

Sulphur,

304.59

13.016

Pt, alloys

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THE SEVEN CRYSTAL SYSTEMS

Name of

Axes

System

Angles

Bravais Lattices

1.

Cubic

a = b = c

:;)

Primitive, Face-centred,

2.

Tetragonal

a= b

:;)

Primitive, Body centred = 2

:;)

Primitive, Face-centred,

c

3.

Rhombohedral

a = b= c

4.

Orthorhombic

a

b

Monoclinic

a

b

c

Triclinic

a

b

c

or Trigonal

or Rhombic

5. 6.

7.

Hexagonal

Unit cell

a=b

c

Body centred cubic

r =

Face centred

r =

cubic

:;)