Answer
The As-I bond length is estimated to be $2.58$ angstrom.
The estimated bond length is a little higher than the experimental bond length $2.55$ angstrom.
Work Step by Step
*Steps to answer:
1) Find out the bonding atomic radii of As and I from figure 7.7
2) Add these two bonding atomic radii to estimate the bonding length in As-I.
1) According to figure, the bonding atomic radii of As is $1.19$ angstrom and that of I is $1.39$ angstrom.
2) The As-I bond length, as a result, would be estimated to be $$1.19+1.39=2.58$$ (angstrom)
The estimated bond length is a little higher than the experimental bond length $2.55$ angstrom.
