`{:("Bond" ,"Bond dissociation energy" ("kJ mole"^(–1))),( C-I ,240 " "to "Element A"),( C-II ,328 " "to "Element B"), (C-III, 276 " "to "Element C"),( C-IV ,485 " "to "Element D"):}`
Elements A, B, C and D, which element has the smallest atom ?

Options

A. I
B. III
C. II
D. IV

Answer

To determine which element among A, B, C, and D has the smallest atomic size based on the bond dissociation energies provided, we can follow these steps:

### Step 1: Understand Bond Dissociation Energy
Bond dissociation energy is the amount of energy required to break a bond between two atoms. A higher bond dissociation energy indicates a stronger bond, which typically correlates with smaller atomic size because smaller atoms can form stronger bonds due to shorter bond lengths.

### Step 2: List the Bond Dissociation Energies
From the question, we have the following bond dissociation energies:
- Element A (C-I): 240 kJ/mol
- Element B (C-II): 328 kJ/mol
- Element C (C-III): 276 kJ/mol
- Element D (C-IV): 485 kJ/mol

### Step 3: Compare the Bond Dissociation Energies
Now, we will compare the bond dissociation energies to identify which element has the highest value:
- Element A: 240 kJ/mol
- Element B: 328 kJ/mol
- Element C: 276 kJ/mol
- Element D: 485 kJ/mol

### Step 4: Identify the Element with the Highest Energy
From the comparison, we see that Element D has the highest bond dissociation energy at 485 kJ/mol.

### Step 5: Conclusion
Since the bond dissociation energy is inversely related to atomic size, the element with the highest bond dissociation energy (Element D) must have the smallest atomic size.

### Final Answer
Element D has the smallest atomic size.

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