### <Success>d and f-Block elements</Success> ### <Success>Lecture-2</Success> <div style='float: left; width:50%;'> </div> <div style='float: right; width:50%;'> <!----> </div>

### <Success>Enthalpy of atomization</Success> <div style='float: left; width:50%;font-size:30px;text-align:left'> <p><strong>Atomic enthalpy</strong></p> <ul> <li>High melting point</li> <li>High boiling point</li> </ul> </div> <div style='float: right; width:50%;font-size:30px;text-align:left;'> <p>$\quad \quad \quad$ <strong>Enthalpy atomization</strong></p> <table> <thead> <tr> <th>Group</th> <th>${C}^{o}$</th> </tr> </thead> <tbody> <tr> <td>Cr</td> <td>1903</td> </tr> <tr> <td>MO</td> <td>2620</td> </tr> <tr> <td>W</td> <td>3410</td> </tr> </tbody> </table> <!----> </div> <div style='float: left; width:100%;font-size:30px;text-align:left'> <ul> <li> <p>Zn, Cd,Hg are not class of the d block elements so they will have law melting point</p> </li> <li> <p>$Zn \rightarrow 419{C}^{o}$</p> </li> <li> <p>$Cd \rightarrow 321{C}^{o}$</p> </li> <li> <p>$Hg \rightarrow -38{C}^{o}$</p> </li> </ul> </div>

### <Success>d-block elements</Success> <div style='float: left; width:100%;font-size:30px;text-align:left'> <ul> <li>They have distinct chemical characteristics resulting from progressive filling of the $d$-shells</li> </ul> <p><strong>Occurrence of variable oxidation states</strong></p> <ul> <li>Give compounds from corresponding ions with structures and physical properties originate from partially filled $d$-orbitals</li> </ul> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/chemistry-class-12-unit-08-chapter-02-d-and-f-block-elements-l-2_5-tn-tykuzp_g-64.jpg"></p> </div>

### <Success>Physical properties</Success> <div style='float: left; width:50%;font-size:25px;text-align:left'> <ul> <li>They have high enthalpies of atomization</li> <li>Maxima in the middle indicate that one unpaired electron per $d$-orbital lead to strong interatomic interaction</li> <li>Greater the number of valence electrons, stronger the bonding</li> <li>Cr,Mo,W have strongest metallic bonding</li> <li>Enthalpy of atomization also contribute to is standard electrode potential of a metal</li> <li>Metals with very high enthalpy of atomization (i.e., very high boiling point) are noble</li> </ul> </div> <div style='float: right; width:50%;'> <p><img alt="alt text" src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/5b103c57-1c5e-4fd8-0fd2-0e48b8aada00/public"></p> <!----> </div>

### <Success>Trends in physical properties</Success> <div style='float: left; width:0%;font-size:30px;text-align:left'> <!--* ${Sc}^{o},{Ti}^{o},V^{o}$ are known as early elements and they are thermodynamicaly reactive--> <!--* They can undergo oxidised form example ${Sc}^{+1},{Sc}^{+2},{Sc}^{+3}$--> <!--* React with $F^{-}$ and form Fluoride minerals--> <!--* React with $Cl^{-}$ and form chloride minerals--> <!--* They are harder anions--> <!--* Noble metlas are less reactive and remain in the metallic state --> <!--* 4d, and 5d series have high atomization energies--> <!-- - Ru, Rh , Pd --> <!-- - Os, Ir, Pt--> </div> <div style='float: center; width:100%;'> <p><img alt="alt text" src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/8c1924fa-b058-43c3-5031-b67f1851c900/public"></p> <!--.jpg)--> </div>

### <Success>Physical properties</Success> <div style='float: left; width:100%;font-size:30px;text-align:left'> <ul> <li>The strength of metallic bonding in tungsten is such that its melting point $\left(3410^{\circ} \mathrm{C}\right)$ is exceeded by only one other element, carbon</li> <li>With increase in principal quantum number the spatial extent of $d$ orbitals increases leading to greater orbital overlap: $5 \mathrm{d}-5 \mathrm{d}>4 \mathrm{d}- 4 \mathrm{d}>3 \mathrm{d}-3 \mathrm{d}$</li> <li>The heavier metals thus exhibit many more compounds containing $\mathrm{M}-\mathrm{M}$ bonds</li> </ul> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/chemistry-class-12-unit-08-chapter-02-d-and-f-block-elements-l-2_5-tn-tykuzp_g-163.jpg"></p> </div>

### <Success>Metalic bonding</Success> <div style='float: left; width:0%;font-size:30px;text-align:left'> <!--* In $M{Cl}_2$ metal is in +2 oxidation state--> <!--* $M{Cl}_3$ metal is in +3 oxidation state--> <!--* $\underbrace {NiCl_2, PdCl_2, PtCl_2} _ {solid}$--> <!--* When these dissolved in water we get metal ion and ligand--> <!--* For example $NiCl_2$ in water gives $Ni^{+2}$ and $Cl^{-}$ but we does not have information about Ni-Cl bond--> <!--* On further dissolution it will give $NiCl^{2-}_4$--> </div> <div style='float: right; width:100%;'> <p><img alt="alt text" src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/258cd476-54c6-499f-50b9-b96de3dd2800/public"></p> <!----> </div>

### <Success>Physical properties</Success> <div style='float: left; width:100%;font-size:30px;text-align:left'> <ul> <li>Ions of the same charge in a given series show progressive decrease in radius with increasing atomic number</li> <li>This is because the new electron enters a $d$ orbital each time the nuclear charge increases by unity</li> <li>It may be recalled that the shielding effect of a $d$-electron is not that effective</li> <li>The same trend is observed in the atomic radii of a given series. However, the variation within a series is quite small</li> </ul> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/chemistry-class-12-unit-08-chapter-02-d-and-f-block-elements-l-2_5-tn-tykuzp_g-189.jpg"></p> </div>

#### <Success>Variation in atomic sizes of transition metals</Success> <div style='float: left; width:70%;font-size:30px;text-align:left'> <ul> <li>An increase from the first $(3 d)$ to the second $(4 d)$ series of the elements but the radii of the third $(5 d)$ scries are virtually the same as those of the corresponding members of the second series</li> <li>Associated with the intervention of the 4f orbitals filled before the $5 d$ series</li> <li>The filling of $4f$ before $5d$ orbital results in a regular decrease in atomic radii <strong>Lanthanoid contraction</strong></li> </ul> </div> <div style='float: right; width:30%;'> <!----> <p><img alt="alt text" src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/bca73e34-c820-4a25-f0d2-053b88ab0900/public"></p> </div>

#### <Success>Consequence of the lanthanoid contraction</Success> <div style='float: left; width:100%;font-size:30px;text-align:left'> <ul> <li>The second and the third $d$ series exhibit similar radii (e.g.,Zr 160 pm, Hf 159 pm) similar physical and chemical properties than that expected on the basis of usual family relationship</li> </ul> <p>Density/g $\mathrm{cm}^3$ $\hspace{2 mm}$ 3.43 $\hspace{2 mm}$ 4.1 $\hspace{2 mm}$ 6.07 $\hspace{2 mm}$ 7.19 $\hspace{2 mm}$ 7.21 $\hspace{2 mm}$ 7.8 $\hspace{2 mm}$ 8.7 $\hspace{2 mm}$ 8.9 $\hspace{2 mm}$ 8.9 $\hspace{2 mm}$ 7.1</p> <ul> <li>The decrease in metallic radius coupled with increase in atomic mass results in a general increase in the density of these elements</li> <li>From titanium (Z=22) to copper (Z=29) significant inerease in the density</li> </ul> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/chemistry-class-12-unit-08-chapter-02-d-and-f-block-elements-l-2_5-tn-tykuzp_g-196.jpg"></p> </div>

## <Success>Thank you</Success> <div style='float: left; width:50%;'> </div> <div style='float: right; width:50%;'> <!----> </div>