- Boyle's Law 
 PV = constant [at constant n , T] ∴ P1V1 = P2V2
- Charle's Law VT= constant [at constant n , P] ∴V1T1=V2T2
 Vt = Vo ( 1 + t / 273 ) [T(kelvin = 273 + t(oC)]
- Gay-Lussac's Law PT= constant [at constant n , V] ∴P1T1=P2T2
- Ideal Gas Eqaution PVnT= R = 0.0821 l . atm . K-1 . mol-1
 = 1.987 Cal K-1 . mol-1 = 8.314 J K-1 . mol-1
 1 atm = 760 mm of Hg = 76 cm of Hg = 101325 pascal ; 1 bar = 0.9863 atm
 Satnadard Temperature and Pressure (STP) or Normal Temperature and Pressure (NTP)
 P = 1 atm , T = 0oC or 273 K
- Density and Molar Mass Relation 
 Density (D) =PMRT
- Dalton's law of Partial Pressure 
 PTotal = P1 + P2 + P3 + .....
 where P1,P2,P3, .... etc are partial pressures of individual gases .
 Partial Pressure = Total pressure x mole function
 Relative humidity =Partial pressure of water in airVapour pressure of water
 Vap. Pressure of dry gas = Vap. Pressure of wet gas - Vap. pressure of water vapour (aqu. Tension)
- Graham's Law (Diffusion and Effusion)(rA) Rate of effusion of gas A(rB) Rate of effusion of gas B=√ρB√ρA=√MB√MA[at constant pressure](rA) Rate of effusion of gas A(rB) Rate of effusion of gas B=PAPB√ρB√ρA=PAPB√MB√MA[at different pressure]
- Velocity of Molecules /phy1.jpg) 
- Real Gases , compressibility Factor
 Z =PVnRT
 Z measures the extent of non - idealness of an ideal gas .
 Z < 1 , implies that gas is more compressible
 Z > 1 , implies that gas is less compressible
 Z = 1 , implies that gas is ideal
- Gas Equation (van der Waal's) /phy2.jpg) 
- Nature of Gas Constant R 
 R =PVnT=Pressure x VolumeMoles x Degree(K)=(Force / Area) x VolumeMoles x Degree(K)=Force x LengthMoles x Degree(K)= Work Done per degree per mole
- Units of Gas constant (R)
 R = 0.0821 atm L K-1 mol-1 = 0.0821 atm dm3 K-1 mol-1
 (Here P = 1atm , V = 22.4 L , T = 273K , 1 L = 1 dm-1)
 If P is expressed in dynes per square centimeter (P = 76 x 981 x 13.6 dyne/cm2)
 V = 22400 dm3 and T = 273 K
 then R = 8.314 x 107 ergs K-1 mol-1 = 8.314 JK-1 mol-1 and R = 1.987 cal K-1 mol-1
 1 atm pressure = 0.76 m x 13.6 x 103 kg m-3 x9.81 ms-2 = 101.325 x 103 Nm-2 = 101.325 x 103 Pa
 1 Nm-2 = 1 Pa
 Thus , the gas constant R =(101.325 x 103 Nm-2) x (22400 x 10-6m3)(273K) x (1 mol)= 8.314 x NmK-1 mol-1 = 5.189 x 1019 eVK-1 mol -1
 [ 1eV = 1.602 x 10-19 volts coulomb (Joule) ]
- Avogadro's Law
 V α n or V α N (at constant T,P)
- Calculation of Kinectic Energy
 Acoording to gas equation , Pv =13Mu2 for 1 mole of gas
 or PV =2312Mu2 for 1 mole of gas
 K.E. =12=32PV =32RT
 For molecule , the KE =32RTNo=32KT
 K(Boltzman constant) =RNo
- Average molecular weight of a gaseous mixture 
 Mmix =Σ niMiΣ ni, where ni is the number of moles and Mi is the molecular weight of the component.
- Critical Pressure (PC) = a27b2
- Critical Temperature (TC) = 8a27Rb
- Critical Volume (VC) = 3b
- Relation between PC , VC and TC : PCVCRTC=38
- Boyle's Temperature (TB) = abR
Sunday, March 30, 2014
STATES OF MATTER
REDOX REACTIONS AND ELECTROCHEMISTRY
- Ecell = Eocell - log[Products][Reactant]
 - Δ G = nFEcell ; - Δ Go = nFEocell
 Eocell =2.303 RTn Flog Keq =0.591nlog Keq [at 250C]
 Δ Go = - 2.303 RT logK
- Gibb's Helmholtz Equation/phy14.jpg) 
- Faraday's First Law
 w = Z i t , 1 faraday is the quantity of charge carried by 1 mole of electrons.
 Z =equivalent mass96500; Z = weight deposited when 1A passed for 1 sec.
- Faraday's second Lawm1m2=E1E2
 m1 , m2 are masses deposited and E1 and E2 are their equivalent weights ; for same amount of passed charge .
 %current efficieny =Actual CurrentAmmeter currentx 100
 Ohm's Law = I = E/R
 Ions are always discharged / produced in equivalent amounts whatever their speeds of deposition are ,
 Specific conductance = κ = 1 / ρ , ρ = specific resistance
 ρ =lax Cla= constant , C = conductance =1R
 Conductivity = cell constant x observed conductance
 πeq =kCeq=K x 1000 cm3 L-1Normality
- Equivalent conductance , (Λ)
 Λ = κ x V
 V = volume in mL containing 1g equivalent of the electrolyte.
 Molar conductance (μ) = [Equivalent conductance]
 (μ) = nΛ
 n =Molecular MassEquivalent Mass
 μ = κ x V V(mL) containing 1g mole of an electrolyte.
 At infinite dilution , Λo = λa + λc
 λc = kuc
 λa = kua
 λa and λc , ionic conductance of anion and cation
 k = 96500C
 ua = mobility of anion
 ua = mobility of cations
 degree of dissociation = Λ / Λ∞
 α = ( K / C)1/2 =λeCλe∞=λmCλμ∞
 λeC , λmC = equivalent and molar conductance
- Ostwald's Equation
 K =C( λmC )2λm∞ (λm∞ - λmC)
- Cell Notation/phy15.jpg) 
 Transport Number
 Transport Number =Current carried by ionToatl current carried
 nc + na = 1
ATOMIC STRUCTURE
- Planck's Quantum Theory
 E = hν =hcλ
 where h = Planck's Constant (6.023 x 10-34 Js) , ν = Frequency of radiation , c = Velocity of Light , λ = Wavelength of radiation
 c = νλ and wave number =1λ
- Moseley's Equation
 √ν = a (z - b)
- Heisenberg's uncertainity Equation
 Δp . Δx ≥h4πand ΔE . Δt ≥h4π
 Kinetic Energy of electron in the nth quantum state =12Zke2rn
 Potential Energy of electron in the nth quantum state = -Zke2rn
 Total energy (E) = -Zke22rn= -(13.6)Z2n2eV per atom
 = -313.6n2kcal / mol = -1312n2kJ / mol
 = - 21.8 x 10-19Z2n2J / atom
- Radius of nth quantum state = n2h24π2mkZe2=n2aoZ(ao = 0.529 A)
- Velocity of electron (vn) = 2ρZke2nh=Znx 2.188 x 106 m/s
 No. of revolutions per second in r.p.s. =vn2πrn=Zvn2πn2ao
 Wave number of spectral line ,/phy3.jpg) 
- de Broglie Equation 
 Azimuthal (or angular) Quantum number (l) ; 0 ≤ l ≤ n - 1
 Orbital angular momentum , L = √l ( l + 1 )h2π
 Magnetic quantum number (m); - l ≤ m ≤ l , total (2l + 1)
 Magnetic Moment , μL =eh4πmc√l ( l + 1 )
 Spin angular momentum = √s( s + 1 )h2π
- Aufbau Principle 
 Subshell qith lowest (n + l) , value is filled first , if two subshells have same (n + l) value , lower value of 'n' is filled up first .
- Photoelectric Effect 
 Maximum kinectic energy of ejected electron12mv2max = hν - hνo
 Stopping Potential , eV = hν - hνo
 Binding Energy = Mass Effect x 931 MeV- Radius of Nucleus (rn) = ro x A1/3 , where A is the mass number and ro is proportionality constant whose value is 1.4 x 10-13 cm
- Although energy of electron increases with the increase in the value of n (orbit) , yet the difference of energy between successive orbits decreases .
 Thus , E2 - E1 > E3 - E2 > E4 - E3 > E5 - E4....etc.
- No. of spectral lines when electron comes from nth level to ground level = n (n + 1)/2
- No. of sub-shells in a main energy level = n
- No. of orbitals in a main energy level = n2
- No .of orbitals in a sub shell = (2l+1)
- No. of electron in each orbit = 2
- Maximum no. of electron in a sub shell = 2 (2l+1)
- Maximum no. of electron in a main shell = 2n2
 
CHEMICAL AND IONIC EQUILIBRIUM
- Equilibrium in Water : /phy10.jpg) - Equilibrium Constant , K = [C]c[D]d[A]a[B]b=kforwardkbackward= KC
- In terms of partial pressure
 Equilibrium Constant , Kp =pCc pDdpAa pBb= Kc (RT)Δng [Δng = np - nr]
 
- Equilibrium Constant , K = 
- Van't Hoff Equation : /phy11.jpg) 
- Gibb's Free Energy 
 ΔG = Δ - TΔS
 ΔGo = - 2.303 RT log10K
- Buffer : 
 pH = pKa + log[conjugate base][acid]
 pOH = pKb + log[conjugate acid][base]
 Mixture of weak acids = ( k1c1 +k2c2 )1/2
 α =% conjugation100/phy12.jpg) 
 ∴ Ksp = [Ay+] x [Bx-] y
- Arrhenius Concept : 
 Substance which give H+ ions when dissolved in water are called acids , while gives OH- ions are called bases.
- Bronsted Lowry Concept : 
 Acid donates proton , base accepts ptoton.
- Ostwald's Dilution Law : 
 α = ( K / C)1/2
 K = dissociation constant of weak electrolyte
 C = Concerntatation
 α = degree of dissociation
 KW = [H+ ][OH- ]
- Hydrolysis Constant : 
 Kh =h2C1 - h
 h =amount of salt hydrolysedTotal salt taken
THERMODYNAMICS
- Mechanical Work
 W = - Pext (ΔV) [during expansion]
- First Law of Thermodynamics
 ΔE = q + W
 ΔE = q - PΔV
- Adiabatic Change/phy6.jpg) 
- Isochoric Change
 ΔV = 0
 W = PΔV = 0
 ΔE = q + W = q
- Cyclic Change (reversible)
 ΔE = 0
 q = -W = PΔV
 q = -Wmax = P∫dV
- Isothermal reversible Expansion
 ΔH = ΔE = 0 (internal energy is a function of temperature)
 q = -Wmax = 2.303 nRT log( V2 / V1) = 2.303 nRT log( P1 / P2)
 ΔH = ΔE + ΔngRT
- Joule - Thompson coefficient /phy7.jpg) 
 (i) For cooling , u > 0 (-ve sign)
 (ii)For heating , u < 0 (+ve sign)
- Second Law of Thermodynamics 
 Efficiency of the Carnot engine = η =q2 - q1q2=T2 - T1T2= 1 -T1T2
 q2 = heat absorbed by engine
 q1 = heat lost to sink
- Entropy Change 
 ΔStotal = ΔSsystem + ΔSsurrounding
 ΔSfusion =ΔHfusionTfusion; ΔSvapour =ΔHvapourTvapour
- Gibb's Free Energy (G)
 ΔG = G2 - G1
 ΔG = ΔH - TΔS (Gibb's Helmholtz equation)
 ΔG < 0 (means spontaneous process)
 ΔG > 0 (means non-spontaneous process)
 ΔG = 0 (means system is at equilibrium)
- Kirchoff's EquationΔH2 - ΔH1T2 - T1= ΔCp andΔE2 - ΔE1T2 - T1= ΔCv
 where , ΔCp = ∑Cp(products) - ∑Cp(reactants) and ΔCv = ∑Cv(products) - ∑Cv(reactants)
- Degree of Dissociation (x)
 x =D - dd=Mt - MoMo
 where , D = theoretical V.D. and d = observed V.D.
- pH of a solution
 pH = -log[H3O+]
 pOH = -log[OH-]
 pH + pOH = pKW = 14
- Isothermal (reversible)
 ΔS = 2.303 nR log (V2 / V1)
 at constant pressure ,
 ΔS = 2.303 Cp log10 (T2 / T1)
 For vaporization ,
 ΔS =ΔHvapTbp
 ΔGo = - nFE0cell
- Sign Convention- If work is done on the system , W is +ve.
- If work is done by the system , W is -ve.
- If heat is absorbed by the system , or ΔH is +ve.
- If heat is given out by the system , q or ΔH is -ve.
- If energy is absorbed by the system , i.e. internal energy increases , ΔE is +ve.
- If energy is released i.e., internal energy of the system decreases , ΔE is -ve.
 
- Heat Capacity
 (i) Heat capacity at constant volume , CV = [ ∂E / ∂T ]V
 (ii) Heat capacity at constant pressure , Cp = [ ∂H / ∂T ]p
 For an ideal gas , Cp - Cv = R
- Heat of Reaction
 ΔH = ∑ H(p) - ∑ H(R)
 For exothermic reaction : ∑ H(p) < ∑ H(R) (∴ Δ is -ve)
 For endothermic reaction : ∑ H(p) > ∑ H(R) (∴ Δ is +ve)
 Heat change at constant pressure = qp = ΔH
 Heat change at constant volume = qv = ΔH
 ΔH = ΔU + PΔV
 ΔH = ΔU + Δn(g)RT
 If,
 Δn(g) = 0 , ΔH = ΔU
 Δn(g) > 0 , ΔH > ΔU
 Δn(g) < 0 , ΔH < ΔU
- Clausis - Clapeyron Equation/phy8.jpg) 
 where ΔHv = molar heat of vapourisation- Calorific Value is the amount of heat evolved when one gram of fuel as food is burnt in the presence of air or excess of oxygen.
- Joule's Relationship between work done (w) and heat produced (H)
 W α H or W = JH
 where J = mechanical equivalent of heat ; J = 4.184 JCal-1
- S1 and S2 are solubility at temperature T1 and T2 respectively
 
SOLUTIONS
- Solubility
 ΔHsolution = ΔHlattice - ΔHhydration
 If hydration energy > lattice energy , the solute goes into solution and ΔHsolution comes out to be -ve value i.e., the process is exothermic.
- Henry's Law
 Mass of the gas dissolved per unit volume (n) α pressure (P)
- Parts per million
 ppm (A) =Mass of ATotal mass of the solutionx 106
 Weigth % = wt. of solute per 100gm of solution
 Volume % = wt. of solute per 100ml Of solution or Volume of solute per 100ml of solution
 Mole % =Mass of soluteMoles of solute + Moles of solventx 100
- Relationship between Molality(m) of a solution and Mole fraction of the solute (X2)
 X2 =m M11 + m M1, where M1 is the molecular mass of the solvent
- Relationship between Molality(m) , Molarity (M) and Density of a solution (d)
 Molality , m =M1000d - MM2x 1000 , where M2 is the molar mass of the solute .
- Relationship between Mole fraction of the solute (x2) and Molarity (M) of the solution
 X2 =MM1M(M1 - M2) + d
 where M1 & M2 are the molecular masses of solvent and solute respectively . Density of solution is d. For isotonic or iso-osmotic solutions .
- Raoult's Law (Vapour - Pressure lowering of solution)
 ps = po.Xsolventpo - psps=nN
 po = pressure of pure solvent ; ps = pressure of solvent
 α , during dissociation ,
 α =i - 1n - 1, n = no. of ions after dissociation
 α , during association ,
 α =1 - i1 - (1/n)
 Variation of vapour pressure with temperature/phy4.jpg) 
 Variation of vapour pressure with external pressure/phy5.jpg) 
- Osmotic Pressure
 π = iniVRT = hdg (due to association or dissociation)
- Van't Hoff Factor
 i =PobservedPnormal=(Δp)observed(Δp)normal=(ΔTb)observed(ΔTb)normal=(ΔTf)observed(ΔTf)normal=Normal molecular massObserved molecular mass
 For solution showing dissociation , the Van't Hoff factor i > 1
 For solution showing association , the Van't Hoff factor i < 1
 For solution showing no dissociation or association, the Van't Hoff factor i = 1
- Raoult's Law
 P = PA + PB = PA0 XA + PB0 XB = ( 1 - X )PA0 + PB0 XB
- Ideal Solutions
 They obey Raoult's law for all range of concerntatation and temperature. ΔHmix = 0 and ΔVmix = 0
 eg. Hexane + Heptane ; Ethyl bromide + Ethyl chlroride ; Chlorobenzene + Bromobenzene , etc..
- Non - Ideal Solutions
 The non-ideal solution do not obey Raoult's law for all concerntatation.
 ΔHmix ≠ 0 and ΔVmix ≠ 0
 If ΔHmix > 0 and ΔVmix > 0 , then non-ideal solutions show +ve deviations.
 If ΔHmix < 0 and ΔVmix < 0 , then non-ideal solutions show +ve deviations.
 e.g. Acetone + ethyl alcohol , water + ethyl alcohol , CCl4 + CHCl3 , etc.
- Types of Azeotropic Mixtures
 (i) Minimum Boiling Azeotropic
 eg:- Ethanol (95.5%) + water(4.5%) mixture boiling .
 (ii) Maximum Boiling Azeotropic
 eg:- HNO3 (68%) + water(32%) mixture boiling at 393.5K .
- Elevation in boiling Point
 ΔTb = Tb - To = Kb m =KB x WB x 1000MB x WA
 WA = mass of solvent (g) ; WB = mass of solute (g)
- Molal depression Constant (Kf)
 Kf =RTf21000Lf[Lf = latent heat of fusion]
 Note :- Above equation are valid only when Kf and Kb are expressed in Kelvin m-1
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