Question

Which of the following pairs of elements would have a more negative electron gain enthalpy?? and give reasons ....
1. F or Cl
2.O or F

Answer 1

In the first group, Cl will be more electronegative because as we move from Cl to F the atomic size increases. This leads to repulsion among the electrons so the electronegativity of F decreases.

But in the second pair F is more electron than O this can be explained in terms of the smaller size of F atoms and increased nuclear charge which is more than that of O even after a slight decrease due to the forces of repulsion as explained above.

Answer 2

Answer:

( ii ) F and Cl

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