# Periodic Table Formulas

Support your learning regarding the Concept Periodic Table during your class or for examination with our Periodic Table Formulas provided. Refer to the below outlined Periodic Table Formulae Sheet and Tables as supplements for your preparation. Quickly grasp the Periodic Table Formulae list over here and apply them whenever you need it.

Solve your chemistry problems fastly and efficiently taking the help of Chemistry Formulas and learn about the Concepts without much effort.

## Periodic Table Formula List

Periodic Table is a chart of all the known elements. Get acquainted with the symbols and full names of all the elements in it easily by referring to our Periodic Table Formula Collection. Be strong with the fundamentals of the Periodic Table Concept by accessing our Periodic Table Cheat Sheet. As you start practicing the formulas you will recall them easily along with the names of chemical compounds.

1. Mendeleev’s periodic table was based upon atomic weight & Modern Periodic table is based upon atomic no.

2. General electronic configuration (of outer orbits):

• s-block ⇒ ns1-2
• p-block ⇒ ns2np1-6
• d-block ⇒ (n – 1)d1-10ns1-2,
• f-block ⇒ (n – 2) f1-14 s2 p6 d10 (n – 1) s2p6d0 or 1ns2

• In A2, rA = dA-A/2
• In AB, dA-B = rA + rB (If XA ≈ XB)
• Sh comaker & Stevenson formula, dA-B = rA + rB – 0.09 Δx (if XA ≠ XB)

4. VWR > MR > CR & Size of isoelectronic Species Z ↑ r ↓

5. 6. (a) Scale of EN: (b) Xm = 2.8 xp, xp = 0.349 xAR + .744, √xp = 0.2 xs + 0.77 SR
⇒ Stability Ratios

7. % ionic character = 16 Δ + 3.5 Δ2 = 16(xA – xB) + 3.5 (xA – xB)2
(Henny & Smyth formula)

8. • In Pr (r)max = Inert gas element (VWR)
• r ↓ r almost same → r ↑ • Radius of members of 4d & 5d series is almost same r (Lanthanide Contraction)

(ii) Ionisation Potential (IP):
Unit of I.P. = KJ mole-1, eV & 1 eV = 96.5 KJ mol-1 & IP1 < IP2 < IP3 < IP4 …….
If ΔIP ≥ 16 eV then lower oxidation state is stable. & If ΔIP ≤ 11.2 eV then higher oxidation state is stable.
IP ∝ $$\frac{1}{\text { size }} \propto \frac{1}{\text { Screening effect }} \propto \frac{1}{\text { no. of innerelectrons }}$$ ∝ nuclear
charge ∝ Stability
(Stability) ⇒ p6 > d10 > p3 > d5 & (IP) p6 > d10 > p3 > d5
& (IP) 2nd transition series > 3rd transition series.
(IP) He > Li & Tl > In & Pb > Sn & Zn > Ga & w < Zn
& N > O, P > S & Be > B, Mg > Al & First IP of Al = First IP of Ga
IP ∝ $$\frac{1}{\text { Metallic character }} \propto \frac{1}{\text { Re ducing character }} \propto \frac{1}{\text { Reactivity }}$$
$$\propto \frac{1}{\text { Basic Nuture of oxide }} \propto \frac{1}{\text { Basic Nuture of hydroxide }}$$

(iii) Electron Affinity (EA):
EA ∝ $$\frac{1}{\text { size }}$$ ∝ nuclear charge
(EA) N < C < P < Si & EA of IA, IIA & 0 group elements = 0
EA of II period elements < EA of Bonding III period element eg. F < Cl

(iv) (X or EN):
(EN ∝ nuclear attraction ∝ + ye oxidation state ∝ $$\frac{1}{\text { atomicradius }}$$ ∝ % S character). (energy) sp > sp2 > sp3 & (EN) sp > sp2 > sp3
& (Size) sp < sp2 < sp3
(EN of hybrid) CH ≡ CH > CH2 = CH2 > CH3 – CH3
& (acidic nature) CH ≡ CH > CH2 = CH2 > CH3 – CH3
(EN) ⇒ Cation > atom, anion < atom
cr+6 > cr+3 > cr+2, F < F
c > c > c
(EN) ⇒ Si < P < C < N,
H ≤ P
Δ EN ∝ B.E. ∝ $$\frac{1}{\text { Bond Length }}$$ ∝ % ionic character ∝ non metallic
character ∝ BS
EN of inert gas = 0
In 4d & 5d series on moving in the same group EN ↑

10. Some important Points:

• Heaviest of Most Dense Metal = Os
• Hardest metal or Max MP = W