Important Formulas: Physical Chemistry

# Important Physical Chemistry Formulas for JEE and NEET

## Atomic Structure

Estimation of closest distance of approach (derivation) of α-particle :

The radius of a nucleus : R = R0 (A)1/3 cm

Planck's Quantum Theory : Energy of one photon = hv = (hc/λ)

Photoelectric Effect:

### Bohr’s Model for Hydrogen like atoms :

1. mvr = n(h/2π) (Quantization of angular momentum)

Or

Or

### Quantum Numbers:

• Principal quantum number (n) = 1,2, 3, 4 .... to∞.
• Orbital angular momentum of electron in any orbit = nh/2π.
• Azimuthal quantum number (l) = 0 , 1 .... to (n - 1).
• Number of orbitals in a subshell = 2l + 1
• Maximum number of electrons in particular subshell = 2x (2l+ 1)
• Orbital angular momentum L =

## Stoichiometry

• Relative atomic mass (R.A.M)=  Total Number of nucleons
• Y-map

### For gases:

Absolute density (mass/volume) =

Vapour density

Mgas = 2 V.D.

### Concentration terms:

Molarity (M):

Molality (m):

Mole fraction (x):

∴ Mole fraction of solution (x1) = ∴ Mole fraction of solvent (x2) =

% Calculation:

### Derive the following conversion:

1. Mole fraction of solute into molarity of solution M =
2. Molarity into mole fraction x2 =
3. Mole fraction into molality m =
4. Molality into mole fraction x2 =
5. Molality into molarity M =
6. Molarity into Molality m =

M1 and M2 are molar masses of solvent and solute, ρ is density of solution (gm/mL)

M = Molarity (mole/lit.), m = Molality (mole/kg), x1 = Mole fraction of solvent, x2 = Mole fraction of solute

### Calculation of individual oxidation number :

Oxidation Number = number of electrons in the valence shell - number of electrons left after bonding

### Concept of Equivalent weight/Mass:

For elements, equivalent weight (E) =

Equivalent weight (E) =  (v.f. = valency factor)

### Concept of number of equivalents:

No. of equivalents of solute =

No. of equivalents of solute = No. of moles of solute x v.f.

### Normality (N):

Normality = Molarity x v.f.

### Calculation of valency Factor:

n-factor of acid = basicity = no. of H+ ion(s) furnished per molecule of the acid,

n-factor of base = acidity = no. of OH- ion(s) furnised by the base per molecule.

### Volume strength of H2O2:

20V H2O2 means one litre of this sample of H2O2 on decomposition gives 20 It. of O2 gas at S.T.P.

### Calculation of available chlorine from a sample of bleaching powder :

where x = molarity of hypo solution and v = mL. of hypo solution used in titration.

The document Important Physical Chemistry Formulas for JEE and NEET is a part of the NEET Course Chemistry Class 12.
All you need of NEET at this link: NEET

## Chemistry Class 12

135 videos|347 docs|182 tests

## Chemistry Class 12

135 videos|347 docs|182 tests

### Up next

 Explore Courses for NEET exam

### How to Prepare for NEET

Read our guide to prepare for NEET which is created by Toppers & the best Teachers
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev
Related Searches

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

;