Sunday, March 30, 2014

STATES OF MATTER

    1. Boyle's Law 
      PV = constant [at constant n , T]     ∴ P1V1 = P2V2
    2. Charle's Law 
      VT
       = constant [at constant n , P]     ∴ 
      V1T1
       = 
      V2T2

      Vt = Vo ( 1 + t / 273 )     [T(kelvin = 273 + t(oC)]
    3. Gay-Lussac's Law 
      PT
       = constant [at constant n , V]     ∴ 
      P1T1
       = 
      P2T2
    4. 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
    5. Density and Molar Mass Relation 
      Density (D) = 
      PMRT
    6. 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)
    7. Graham's Law (Diffusion and Effusion)
      (rA) Rate of effusion of gas A(rB) Rate of effusion of gas B
       = 
      ρBρA
       = 
      MBMA
       [at constant pressure]
      (rA) Rate of effusion of gas A(rB) Rate of effusion of gas B
       = 
      PAPB
       
      ρBρA
       = 
      PAPB
       
      MBMA
       [at different pressure]
    8. Velocity of Molecules 
    9. 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
    10. Gas Equation (van der Waal's) 
    11. 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
    12. 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) ]
    13. Avogadro's Law
      V α n or V α N (at constant T,P)
    14. Calculation of Kinectic Energy
      Acoording to gas equation , Pv = 
      13
       Mu2 for 1 mole of gas
      or PV = 
      23
      12
       Mu2 for 1 mole of gas
      K.E. = 
      12
       = 
      32
      PV = 
      32
      RT
      For molecule , the KE = 
      32
      RTNo
       = 
      32
      KT
      K(Boltzman constant) = 
      RNo
    15. 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.
    16. Critical Pressure (PC
      a27b2
    17. Critical Temperature (TC
      8a27Rb
    18. Critical Volume (VC= 3b
    19. Relation between PC , VC and TC : 
      PCVCRTC
       = 
      38
    20. Boyle's Temperature (TB
      abR

REDOX REACTIONS AND ELECTROCHEMISTRY

    1. Ecell = Eocell - log
      [Products][Reactant]

      - Δ G = nFEcell ; - Δ Go = nFEocell
      Eocell = 
      2.303 RTn F
       log Keq = 
      0.591n
       log Keq [at 250C]
      Δ Go = - 2.303 RT logK
    2. Gibb's Helmholtz Equation
    3. 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.
    4. Faraday's second Law
      m1m2
       = 
      E1E2

      m1 , m2 are masses deposited and E1 and E2 are their equivalent weights ; for same amount of passed charge .
      %current efficieny = 
      Actual CurrentAmmeter current
       x 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 = 
      la
       x C      
      la
       = constant , C = conductance = 
      1R

      Conductivity = cell constant x observed conductance
      πeq = 
      kCeq
       = 
      K x 1000 cm3 L-1Normality
    5. 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
    6. Ostwald's Equation
      K = 
      C( λmC )2λm (λm - λmC)
    7. Cell Notation

      Transport Number
      Transport Number = 
      Current carried by ionToatl current carried

      nc + na = 1

ATOMIC STRUCTURE

    1. 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
    2. Moseley's Equation
      ν = a (z - b)
    3. Heisenberg's uncertainity Equation
      Δp . Δx ≥ 
      h
       and ΔE . Δt ≥ 
      h

      Kinetic Energy of electron in the nth quantum state = 
      12
       
      Zke2rn

      Potential Energy of electron in the nth quantum state = - 
      Zke2rn

      Total energy (E) = - 
      Zke22rn
       = - 
      (13.6)Z2n2
      eV per atom
                   = - 
      313.6n2
       kcal / mol = - 
      1312n2
       kJ / mol
                   = - 21.8 x 10-19
      Z2n2
       J / atom
    4. Radius of nth quantum state = 
      n2h22mkZe2
       = 
      n2aoZ
      (ao = 0.529 A)
    5. Velocity of electron (vn) = 
      2ρZke2nh
       = 
      Zn
       x 2.188 x 106 m/s
      No. of revolutions per second in r.p.s. = 
      vn2πrn
       = 
      Zvn2πn2ao

      Wave number of spectral line ,
    6. de Broglie Equation 
      Azimuthal (or angular) Quantum number (l) ; 0 ≤ l ≤ n - 1
      Orbital angular momentum , L = l ( l + 1 )
      h

      Magnetic quantum number (m); - l ≤ m ≤ l , total (2l + 1)
      Magnetic Moment , μL = 
      eh4πmc
      l ( l + 1 )
      Spin angular momentum = s( s + 1 )
      h
    7. 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 .
    8. Photoelectric Effect 
      Maximum kinectic energy of ejected electron
      12
       mv2max = 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

    1. Equilibrium in Water : 
      • 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]
    2. Van't Hoff Equation : 
    3. Gibb's Free Energy 
      ΔG = Δ - TΔS
      ΔGo = - 2.303 RT log10K
    4. Buffer : 
      pH = pKa + log 
      [conjugate base][acid]

      pOH = pKb + log 
      [conjugate acid][base]

      Mixture of weak acids = ( k1c1 +k2c2 )1/2
      α = 
      % conjugation100


      ∴ Ksp = [Ay+x [Bx-y
    5. Arrhenius Concept : 
      Substance which give H+ ions when dissolved in water are called acids , while gives OH- ions are called bases.
    6. Bronsted Lowry Concept : 
      Acid donates proton , base accepts ptoton.
    7. Ostwald's Dilution Law : 
      α = ( K / C)1/2
      K = dissociation constant of weak electrolyte
      C = Concerntatation
      α = degree of dissociation
      KW = [H+ ][OH- ]
    8. Hydrolysis Constant : 
      Kh = 
      h2C1 - h

      h = 
      amount of salt hydrolysedTotal salt taken

THERMODYNAMICS

    1. Mechanical Work
      W = - Pext (ΔV) [during expansion]
    2. First Law of Thermodynamics
      ΔE = q + W
      ΔE = q - PΔV
    3. Adiabatic Change
    4. Isochoric Change
      ΔV = 0
      W = PΔV = 0
      ΔE = q + W = q
    5. Cyclic Change (reversible)
      ΔE = 0
      q = -W = PΔV
      q = -Wmax = P∫dV
    6. 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
    7. Joule - Thompson coefficient 

      (i) For cooling , u > 0 (-ve sign)
      (ii)For heating , u < 0 (+ve sign)
    8. 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
    9. Entropy Change 
      ΔStotal = ΔSsystem + ΔSsurrounding
      ΔSfusion = 
      ΔHfusionTfusion
       ; ΔSvapour = 
      ΔHvapourTvapour
    10. 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)
    11. Kirchoff's Equation
      ΔH2 - ΔH1T2 - T1
       = ΔCp and 
      ΔE2 - ΔE1T2 - T1
       = ΔCv
      where , ΔCp = ∑Cp(products) - ∑Cp(reactants) and ΔC= ∑Cv(products) - ∑Cv(reactants)
    12. Degree of Dissociation (x)
      x = 
      D - dd
       = 
      Mt - MoMo

      where , D = theoretical V.D. and d = observed V.D.
    13. pH of a solution
      pH = -log[H3O+]
      pOH = -log[OH-]
      pH + pOH = pKW = 14
    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
    15. 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.
    16. 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
    17. 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
    18. Clausis - Clapeyron Equation

      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

    1. 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.
    2. Henry's Law
      Mass of the gas dissolved per unit volume (n) α pressure (P)
    3. Parts per million
      ppm (A) = 
      Mass of ATotal mass of the solution
       x 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 solvent
       x 100
    4. 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
    5. Relationship between Molality(m) , Molarity (M) and Density of a solution (d)
      Molality , m = 
      M1000d - MM2
       x 1000 , where M2 is the molar mass of the solute .
    6. 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 .
    7. Raoult's Law (Vapour - Pressure lowering of solution)
      ps = po.Xsolvent
      po - 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

      Variation of vapour pressure with external pressure
    8. Osmotic Pressure
      π = i 
      niV
      RT = hdg (due to association or dissociation)
    9. 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
    10. Raoult's Law
      P = PA + PB = PA0 XA + PB0 XB = ( 1 - X )PA0 + PB0 XB
    11. 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..
    12. 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.
    13. 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 .
    14. 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)
    15. 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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