The transition metals exhibit higher enthalphies of atomisation due to :

Options

A. their ability to show variable oxidation states
B. the presence of incompletely filled d-subshell
C. their ability to exist in the solid state with unpaired electrons
D. strong interatomic interaction arises because of having large number of unpaired electrons in their atoms

Answer

To solve the question regarding the higher enthalpies of atomization in transition metals, we can break down the reasoning step-by-step:

### Step 1: Understanding Enthalpy of Atomization
The enthalpy of atomization refers to the energy required to convert one mole of a substance into its gaseous atoms. Higher enthalpy of atomization indicates stronger bonds between atoms in the solid state.

**Hint:** Think about what factors contribute to the strength of bonds in metals.

### Step 2: Characteristics of Transition Metals
Transition metals are known for their unique properties, including the ability to exhibit variable oxidation states and the presence of incompletely filled d-orbitals. These characteristics influence their bonding and stability.

**Hint:** Consider how the electronic configuration of transition metals affects their bonding.

### Step 3: Role of Unpaired Electrons
Transition metals often have unpaired electrons in their d-orbitals. The presence of these unpaired electrons contributes to stronger metallic bonding due to increased interatomic interactions.

**Hint:** Reflect on how unpaired electrons can lead to stronger attractions between atoms.

### Step 4: Comparison with Other Metals
Unlike transition metals, certain metals like zinc, cadmium, and mercury have completely filled d-orbitals. This results in fewer unpaired electrons and thus weaker metallic bonds, leading to lower enthalpies of atomization.

**Hint:** Think about the relationship between electron configuration and bond strength.

### Step 5: Conclusion
The higher enthalpies of atomization in transition metals can be attributed to strong interatomic interactions arising from the large number of unpaired electrons in their atoms. Therefore, the correct answer to the question is that transition metals exhibit higher enthalpies of atomization due to strong interatomic interactions from unpaired electrons.

**Final Answer:** The transition metals exhibit higher enthalpies of atomization due to strong interatomic interactions arising from having a large number of unpaired electrons in their atoms.